benchmarks/build.gradle.kts

@@ -18,9 +18,10 @@ repositories {
 kotlin {
     jvm()
 
-    js(IR) {
+// Testing multi-receiver!
-        nodejs()
+//    js(IR) {
-    }
+//        nodejs()
+//    }
 
     sourceSets {
         all {
@@ -74,7 +75,8 @@ benchmark {
     // Setup configurations
     targets {
         register("jvm")
-        register("js")
+    // Testing multi-receiver!
+    //        register("js")
     }
 
     fun kotlinx.benchmark.gradle.BenchmarkConfiguration.commonConfiguration() {
@@ -158,7 +160,7 @@ kotlin.sourceSets.all {
 tasks.withType<org.jetbrains.kotlin.gradle.dsl.KotlinJvmCompile> {
     kotlinOptions {
         jvmTarget = "11"
-        freeCompilerArgs = freeCompilerArgs + "-Xjvm-default=all" + "-Xlambdas=indy"
+        freeCompilerArgs = freeCompilerArgs + "-Xjvm-default=all" + "-Xlambdas=indy" + "-Xcontext-receivers"
     }
 }
 

benchmarks/src/jvmMain/kotlin/space/kscience/kmath/benchmarks/ExpressionsInterpretersBenchmark.kt

@@ -11,10 +11,7 @@ import kotlinx.benchmark.Scope
 import kotlinx.benchmark.State
 import space.kscience.kmath.asm.compileToExpression
 import space.kscience.kmath.expressions.*
-import space.kscience.kmath.operations.Algebra
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.DoubleField
-import space.kscience.kmath.operations.bindSymbol
-import space.kscience.kmath.operations.invoke
 import kotlin.math.sin
 import kotlin.random.Random
 

build.gradle.kts

@@ -11,7 +11,7 @@ allprojects {
     }
 
     group = "space.kscience"
-    version = "0.3.0-dev-21"
+    version = "0.4.0-dev-1"
 }
 
 subprojects {

buildSrc/gradle.properties

@@ -4,4 +4,4 @@
 #
 
 kotlin.code.style=official
-toolsVersion=0.11.2-kotlin-1.6.10
+toolsVersion=0.11.2-kotlin-1.6.20

buildSrc/src/main/kotlin/space/kscience/kmath/ejml/codegen/ejmlCodegen.kt

@@ -207,7 +207,7 @@ public object EjmlLinearSpace${ops} : EjmlLinearSpace<${type}, ${kmathAlgebra},
         structure.getFeature(type)?.let { return it }
         val origin = structure.toEjml().origin
 
-        return when (type) {
+        return type.cast(when (type) {
         ${
         if (isDense)
             """    InverseMatrixFeature::class -> object : InverseMatrixFeature<${type}> {
@@ -318,8 +318,8 @@ public object EjmlLinearSpace${ops} : EjmlLinearSpace<${type}, ${kmathAlgebra},
             }"""
     }
 
-            else -> null
+            else -> return null
-        }?.let(type::cast)
+        })
     }
 
     /**

docs/algebra.md

@@ -62,10 +62,6 @@ val c2 = ComplexField { c1 - 1.0 } // Returns: Complex(re=0.0, im=2.0)
 val c3 = ComplexField { c1 - i * 2.0 }
 ```
 
-**Note**: In theory it is possible to add behaviors directly to the context, but as for now Kotlin does not support
-that. Watch [KT-10468](https://youtrack.jetbrains.com/issue/KT-10468) and
-[KEEP-176](https://github.com/Kotlin/KEEP/pull/176) for updates.
-
 ## Nested fields
 
 Contexts allow one to build more complex structures. For example, it is possible to create a `Matrix` from complex

examples/build.gradle.kts

@@ -61,7 +61,8 @@ kotlin.sourceSets.all {
 tasks.withType<org.jetbrains.kotlin.gradle.dsl.KotlinJvmCompile> {
     kotlinOptions {
         jvmTarget = "11"
-        freeCompilerArgs = freeCompilerArgs + "-Xjvm-default=all" + "-Xopt-in=kotlin.RequiresOptIn" + "-Xlambdas=indy"
+        freeCompilerArgs =
+            freeCompilerArgs + "-Xjvm-default=all" + "-Xopt-in=kotlin.RequiresOptIn" + "-Xlambdas=indy" + "-Xcontext-receivers"
     }
 }
 

examples/src/main/kotlin/space/kscience/kmath/ast/expressions.kt

@@ -8,8 +8,7 @@ package space.kscience.kmath.ast
 import space.kscience.kmath.asm.compileToExpression
 import space.kscience.kmath.expressions.MstExtendedField
 import space.kscience.kmath.expressions.Symbol.Companion.x
-import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.invoke
 
 fun main() {
     val expr = MstExtendedField {

examples/src/main/kotlin/space/kscience/kmath/fit/chiSquared.kt

@@ -13,6 +13,8 @@ import space.kscience.kmath.distributions.NormalDistribution
 import space.kscience.kmath.expressions.chiSquaredExpression
 import space.kscience.kmath.expressions.symbol
 import space.kscience.kmath.operations.asIterable
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import space.kscience.kmath.operations.toList
 import space.kscience.kmath.optimization.FunctionOptimizationTarget
 import space.kscience.kmath.optimization.optimizeWith

examples/src/main/kotlin/space/kscience/kmath/fit/qowFit.kt

@@ -14,6 +14,8 @@ import space.kscience.kmath.expressions.Symbol
 import space.kscience.kmath.expressions.binding
 import space.kscience.kmath.expressions.symbol
 import space.kscience.kmath.operations.asIterable
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import space.kscience.kmath.operations.toList
 import space.kscience.kmath.optimization.QowOptimizer
 import space.kscience.kmath.optimization.chiSquaredOrNull

examples/src/main/kotlin/space/kscience/kmath/functions/matrixIntegration.kt

@@ -13,6 +13,7 @@ import space.kscience.kmath.nd.structureND
 import space.kscience.kmath.nd.withNdAlgebra
 import space.kscience.kmath.operations.algebra
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.times
 
 fun main(): Unit = Double.algebra {
     withNdAlgebra(2, 2) {

examples/src/main/kotlin/space/kscience/kmath/operations/mixedNDOperations.kt

@@ -7,7 +7,6 @@ package space.kscience.kmath.operations
 
 import space.kscience.kmath.commons.linear.CMLinearSpace
 import space.kscience.kmath.linear.matrix
-import space.kscience.kmath.nd.DoubleBufferND
 import space.kscience.kmath.nd.Shape
 import space.kscience.kmath.nd.Structure2D
 import space.kscience.kmath.nd.ndAlgebra
@@ -21,7 +20,7 @@ fun main() {
 
     val cmMatrix: Structure2D<Double> = CMLinearSpace.matrix(2, 2)(0.0, 1.0, 0.0, 3.0)
 
-    val res: DoubleBufferND = DoubleField.ndAlgebra {
+    val res = DoubleField.ndAlgebra {
         exp(viktorStructure) + 2.0 * cmMatrix
     }
 

examples/src/main/kotlin/space/kscience/kmath/structures/ComplexND.kt

@@ -15,6 +15,8 @@ import space.kscience.kmath.nd.ndAlgebra
 import space.kscience.kmath.nd.structureND
 import space.kscience.kmath.operations.DoubleField
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import kotlin.system.measureTimeMillis
 
 fun main() {

examples/src/main/kotlin/space/kscience/kmath/structures/StreamDoubleFieldND.kt

@@ -80,7 +80,7 @@ class StreamDoubleFieldND(override val shape: IntArray) : FieldND<Double, Double
         return BufferND(strides, array.asBuffer())
     }
 
-    override fun StructureND<Double>.unaryMinus(): StructureND<Double> = map { -it }
+    override fun negate(arg: StructureND<Double>): StructureND<Double> = arg.map { -it }
 
     override fun scale(a: StructureND<Double>, value: Double): StructureND<Double> = a.map { it * value }
 

examples/src/main/kotlin/space/kscience/kmath/structures/buffers.kt

@@ -5,10 +5,7 @@
 
 package space.kscience.kmath.structures
 
-import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.buffer
-import space.kscience.kmath.operations.bufferAlgebra
-import space.kscience.kmath.operations.withSize
 
 inline fun <reified R : Any> MutableBuffer.Companion.same(
     n: Int,

examples/src/main/kotlin/space/kscience/kmath/tensors/OLSWithSVD.kt

@@ -5,12 +5,13 @@
 
 package space.kscience.kmath.tensors
 
+import space.kscience.kmath.nd.StructureND
+import space.kscience.kmath.operations.abs
 import space.kscience.kmath.operations.invoke
-import space.kscience.kmath.tensors.core.DoubleTensor
+import space.kscience.kmath.operations.minus
+import space.kscience.kmath.operations.plus
 import space.kscience.kmath.tensors.core.DoubleTensorAlgebra
 
-import kotlin.math.abs
-
 // OLS estimator using SVD
 
 fun main() {
@@ -48,14 +49,16 @@ fun main() {
 
 
         // inverse Sigma matrix can be restored from singular values with diagonalEmbedding function
-        val sigma = diagonalEmbedding(singValues.map{ if (abs(it) < 1e-3) 0.0 else 1.0/it })
+        val sigma = diagonalEmbedding(singValues.map { if (abs(it) < 1e-3) 0.0 else 1.0 / it })
 
         val alphaOLS = v dot sigma dot u.transpose() dot y
-        println("Estimated alpha:\n" +
+        println(
-                "$alphaOLS")
+            "Estimated alpha:\n" +
+                    "$alphaOLS"
+        )
 
         // figure out MSE of approximation
-        fun mse(yTrue: DoubleTensor, yPred: DoubleTensor): Double {
+        fun mse(yTrue: StructureND<Double>, yPred: StructureND<Double>): Double {
             require(yTrue.shape.size == 1)
             require(yTrue.shape contentEquals yPred.shape)
 

examples/src/main/kotlin/space/kscience/kmath/tensors/PCA.kt

@@ -5,10 +5,11 @@
 
 package space.kscience.kmath.tensors
 
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import space.kscience.kmath.tensors.core.tensorAlgebra
 import space.kscience.kmath.tensors.core.withBroadcast
 
-
 // simple PCA
 
 fun main(): Unit = Double.tensorAlgebra.withBroadcast {  // work in context with broadcast methods

examples/src/main/kotlin/space/kscience/kmath/tensors/dataSetNormalization.kt

@@ -5,10 +5,11 @@
 
 package space.kscience.kmath.tensors
 
+import space.kscience.kmath.operations.div
+import space.kscience.kmath.operations.minus
 import space.kscience.kmath.tensors.core.tensorAlgebra
 import space.kscience.kmath.tensors.core.withBroadcast
 
-
 // Dataset normalization
 
 fun main() = Double.tensorAlgebra.withBroadcast {  // work in context with broadcast methods

examples/src/main/kotlin/space/kscience/kmath/tensors/multik.kt

@@ -10,6 +10,8 @@ import org.jetbrains.kotlinx.multik.api.ndarray
 import space.kscience.kmath.multik.multikAlgebra
 import space.kscience.kmath.nd.one
 import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.minus
+import space.kscience.kmath.operations.plus
 
 fun main(): Unit = with(DoubleField.multikAlgebra) {
     val a = Multik.ndarray(intArrayOf(1, 2, 3)).asType<Double>().wrap()

examples/src/main/kotlin/space/kscience/kmath/tensors/neuralNetwork.kt

@@ -5,11 +5,9 @@
 
 package space.kscience.kmath.tensors
 
-import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.misc.PerformancePitfall
-import space.kscience.kmath.tensors.core.BroadcastDoubleTensorAlgebra
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.tensors.core.DoubleTensor
+import space.kscience.kmath.tensors.core.*
-import space.kscience.kmath.tensors.core.DoubleTensorAlgebra
-import space.kscience.kmath.tensors.core.copyArray
 import kotlin.math.sqrt
 
 const val seed = 100500L
@@ -27,13 +25,10 @@ open class Activation(
     val activation: (DoubleTensor) -> DoubleTensor,
     val activationDer: (DoubleTensor) -> DoubleTensor,
 ) : Layer {
-    override fun forward(input: DoubleTensor): DoubleTensor {
+    override fun forward(input: DoubleTensor): DoubleTensor = activation(input)
-        return activation(input)
-    }
 
-    override fun backward(input: DoubleTensor, outputError: DoubleTensor): DoubleTensor {
+    override fun backward(input: DoubleTensor, outputError: DoubleTensor): DoubleTensor =
-        return DoubleTensorAlgebra { outputError * activationDer(input) }
+        DoubleTensorAlgebra { outputError * activationDer(input) }
-    }
 }
 
 fun relu(x: DoubleTensor): DoubleTensor = DoubleTensorAlgebra {
@@ -106,8 +101,8 @@ fun accuracy(yPred: DoubleTensor, yTrue: DoubleTensor): Double {
 }
 
 // neural network class
-@OptIn(ExperimentalStdlibApi::class)
 class NeuralNetwork(private val layers: List<Layer>) {
+    @OptIn(PerformancePitfall::class)
     private fun softMaxLoss(yPred: DoubleTensor, yTrue: DoubleTensor): DoubleTensor = BroadcastDoubleTensorAlgebra {
 
         val onesForAnswers = yPred.zeroesLike()
@@ -174,7 +169,7 @@ class NeuralNetwork(private val layers: List<Layer>) {
 }
 
 
-@OptIn(ExperimentalStdlibApi::class)
+@OptIn(PerformancePitfall::class)
 fun main() = BroadcastDoubleTensorAlgebra {
     val features = 5
     val sampleSize = 250

kmath-ast/build.gradle.kts

@@ -84,3 +84,8 @@ readme {
         ref = "src/commonMain/kotlin/space/kscience/kmath/ast/rendering/MathRenderer.kt"
     ) { "Extendable MST rendering" }
 }
+
+// Testing multi-receiver!
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile> {
+    enabled = false
+}

kmath-ast/src/commonTest/kotlin/space/kscience/kmath/ast/TestCompilerConsistencyWithInterpreter.kt

@@ -9,9 +9,7 @@ import space.kscience.kmath.expressions.MstField
 import space.kscience.kmath.expressions.MstRing
 import space.kscience.kmath.expressions.Symbol.Companion.x
 import space.kscience.kmath.expressions.interpret
-import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.IntRing
-import space.kscience.kmath.operations.invoke
 import kotlin.test.Test
 import kotlin.test.assertEquals
 

kmath-ast/src/commonTest/kotlin/space/kscience/kmath/ast/TestCompilerOperations.kt

@@ -8,8 +8,7 @@ package space.kscience.kmath.ast
 import space.kscience.kmath.expressions.MstExtendedField
 import space.kscience.kmath.expressions.Symbol.Companion.x
 import space.kscience.kmath.expressions.invoke
-import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.invoke
 import kotlin.test.Test
 import kotlin.test.assertEquals
 

kmath-commons/src/main/kotlin/space/kscience/kmath/commons/expressions/DerivativeStructureExpression.kt

@@ -68,7 +68,7 @@ public class DerivativeStructureField(
 
     public fun DerivativeStructure.derivative(vararg symbols: Symbol): Double = derivative(symbols.toList())
 
-    override fun DerivativeStructure.unaryMinus(): DerivativeStructure = negate()
+    override fun negate(arg: DerivativeStructure): DerivativeStructure = arg.negate()
 
     override fun add(left: DerivativeStructure, right: DerivativeStructure): DerivativeStructure = left.add(right)
 

kmath-commons/src/test/kotlin/space/kscience/kmath/commons/expressions/DerivativeStructureExpressionTest.kt

@@ -6,6 +6,9 @@
 package space.kscience.kmath.commons.expressions
 
 import space.kscience.kmath.expressions.*
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
+import space.kscience.kmath.operations.unaryMinus
 import kotlin.contracts.InvocationKind
 import kotlin.contracts.contract
 import kotlin.test.Test

kmath-commons/src/test/kotlin/space/kscience/kmath/commons/optimization/OptimizeTest.kt

@@ -13,7 +13,7 @@ import space.kscience.kmath.expressions.Symbol.Companion.x
 import space.kscience.kmath.expressions.Symbol.Companion.y
 import space.kscience.kmath.expressions.chiSquaredExpression
 import space.kscience.kmath.expressions.symbol
-import space.kscience.kmath.operations.map
+import space.kscience.kmath.operations.*
 import space.kscience.kmath.optimization.*
 import space.kscience.kmath.stat.RandomGenerator
 import space.kscience.kmath.structures.DoubleBuffer

kmath-complex/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     kotlin("multiplatform")
     id("ru.mipt.npm.gradle.common")
-    id("ru.mipt.npm.gradle.native")
+//    id("ru.mipt.npm.gradle.native")
 }
 
 kotlin.sourceSets {
@@ -29,3 +29,8 @@ readme {
         ref = "src/commonMain/kotlin/space/kscience/kmath/complex/Quaternion.kt"
     )
 }
+
+// Testing multi-receiver!
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile> {
+    enabled = false
+}

kmath-complex/src/commonMain/kotlin/space/kscience/kmath/complex/Complex.kt

@@ -5,6 +5,7 @@
 
 package space.kscience.kmath.complex
 
+import space.kscience.kmath.complex.ComplexField.plus
 import space.kscience.kmath.memory.MemoryReader
 import space.kscience.kmath.memory.MemorySpec
 import space.kscience.kmath.memory.MemoryWriter
@@ -71,14 +72,13 @@ public object ComplexField :
      */
     public val i: Complex by lazy { Complex(0.0, 1.0) }
 
-    override fun Complex.unaryMinus(): Complex = Complex(-re, -im)
 
     override fun number(value: Number): Complex = Complex(value.toDouble(), 0.0)
 
     override fun scale(a: Complex, value: Double): Complex = Complex(a.re * value, a.im * value)
 
     override fun add(left: Complex, right: Complex): Complex = Complex(left.re + right.re, left.im + right.im)
-//    override fun multiply(a: Complex, k: Number): Complex = Complex(a.re * k.toDouble(), a.im * k.toDouble())
+    override fun negate(arg: Complex): Complex = Complex(-arg.re, -arg.im)
 
     override fun multiply(left: Complex, right: Complex): Complex =
         Complex(left.re * right.re - left.im * right.im, left.re * right.im + left.im * right.re)
@@ -107,8 +107,6 @@ public object ComplexField :
         }
     }
 
-    override operator fun Complex.div(k: Number): Complex = Complex(re / k.toDouble(), im / k.toDouble())
-
     override fun sin(arg: Complex): Complex = i * (exp(-i * arg) - exp(i * arg)) / 2.0
     override fun cos(arg: Complex): Complex = (exp(-i * arg) + exp(i * arg)) / 2.0
 
@@ -139,53 +137,58 @@ public object ComplexField :
 
     override fun ln(arg: Complex): Complex = ln(arg.r) + i * atan2(arg.im, arg.re)
 
-    /**
+    override fun norm(arg: Complex): Complex = sqrt(arg.conjugate * arg)
+}
+
+/**
  * Adds complex number to real one.
  *
  * @receiver the augend.
  * @param c the addend.
  * @return the sum.
  */
-    public operator fun Double.plus(c: Complex): Complex = add(this.toComplex(), c)
+context(ComplexField)
+public operator fun Double.plus(c: Complex): Complex = add(toComplex(), c)
 
-    /**
+/**
-     * Subtracts complex number from real one.
-     *
-     * @receiver the minuend.
-     * @param c the subtrahend.
-     * @return the difference.
-     */
-    public operator fun Double.minus(c: Complex): Complex = add(this.toComplex(), -c)
-
-    /**
  * Adds real number to complex one.
  *
  * @receiver the augend.
  * @param d the addend.
  * @return the sum.
  */
-    public operator fun Complex.plus(d: Double): Complex = d + this
+context(ComplexField)
+public operator fun Complex.plus(d: Double): Complex = d + this
 
-    /**
+/**
+ * Subtracts complex number from real one.
+ *
+ * @receiver the minuend.
+ * @param c the subtrahend.
+ * @return the difference.
+ */
+context(ComplexField)
+public operator fun Double.minus(c: Complex): Complex = add(toComplex(), -c)
+
+/**
  * Subtracts real number from complex one.
  *
  * @receiver the minuend.
  * @param d the subtrahend.
  * @return the difference.
  */
-    public operator fun Complex.minus(d: Double): Complex = add(this, -d.toComplex())
+context(ComplexField)
+public operator fun Complex.minus(d: Double): Complex = add(this, -d.toComplex())
 
-    /**
+/**
  * Multiplies real number by complex one.
  *
  * @receiver the multiplier.
  * @param c the multiplicand.
  * @receiver the product.
  */
-    public operator fun Double.times(c: Complex): Complex = Complex(c.re * this, c.im * this)
+context(ComplexField)
-
+public operator fun Double.times(c: Complex): Complex = Complex(c.re * this, c.im * this)
-    override fun norm(arg: Complex): Complex = sqrt(arg.conjugate * arg)
-}
 
 /**
  * Represents `double`-based complex number.
@@ -193,7 +196,6 @@ public object ComplexField :
  * @property re The real part.
  * @property im The imaginary part.
  */
-@OptIn(UnstableKMathAPI::class)
 public data class Complex(val re: Double, val im: Double) {
     public constructor(re: Number, im: Number) : this(re.toDouble(), im.toDouble())
     public constructor(re: Number) : this(re.toDouble(), 0.0)

kmath-complex/src/commonMain/kotlin/space/kscience/kmath/complex/Quaternion.kt

@@ -166,10 +166,7 @@ public object QuaternionField : Field<Quaternion>, Norm<Quaternion, Quaternion>,
     override operator fun Quaternion.plus(other: Number): Quaternion = Quaternion(w + other.toDouble(), x, y, z)
     override operator fun Quaternion.minus(other: Number): Quaternion = Quaternion(w - other.toDouble(), x, y, z)
 
-    override operator fun Number.times(arg: Quaternion): Quaternion =
+    override fun negate(arg: Quaternion): Quaternion = Quaternion(-arg.w, -arg.x, -arg.y, -arg.z)
-        Quaternion(toDouble() * arg.w, toDouble() * arg.x, toDouble() * arg.y, toDouble() * arg.z)
-
-    override fun Quaternion.unaryMinus(): Quaternion = Quaternion(-w, -x, -y, -z)
     override fun norm(arg: Quaternion): Quaternion = sqrt(arg.conjugate * arg)
 
     override fun bindSymbolOrNull(value: String): Quaternion? = when (value) {

kmath-complex/src/commonTest/kotlin/space/kscience/kmath/complex/ComplexFieldTest.kt

@@ -5,7 +5,7 @@
 
 package space.kscience.kmath.complex
 
-import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.*
 import kotlin.math.PI
 import kotlin.math.abs
 import kotlin.test.Test

kmath-complex/src/commonTest/kotlin/space/kscience/kmath/complex/ComplexTest.kt

@@ -6,6 +6,8 @@
 package space.kscience.kmath.complex
 
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.minus
+import space.kscience.kmath.operations.plus
 import kotlin.math.sqrt
 import kotlin.test.Test
 import kotlin.test.assertEquals

kmath-complex/src/commonTest/kotlin/space/kscience/kmath/complex/ExpressionFieldForComplexTest.kt

@@ -9,6 +9,8 @@ import space.kscience.kmath.expressions.FunctionalExpressionField
 import space.kscience.kmath.expressions.invoke
 import space.kscience.kmath.expressions.symbol
 import space.kscience.kmath.operations.bindSymbol
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import kotlin.test.Test
 import kotlin.test.assertEquals
 

kmath-complex/src/commonTest/kotlin/space/kscience/kmath/complex/QuaternionFieldTest.kt

@@ -6,6 +6,8 @@
 package space.kscience.kmath.complex
 
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import kotlin.test.Test
 import kotlin.test.assertEquals
 

kmath-core/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     kotlin("multiplatform")
     id("ru.mipt.npm.gradle.common")
-    id("ru.mipt.npm.gradle.native")
+//    id("ru.mipt.npm.gradle.native")
 //    id("com.xcporter.metaview") version "0.0.5"
 }
 
@@ -72,3 +72,8 @@ readme {
         ref = "src/commonMain/kotlin/space/kscience/kmath/expressions/SimpleAutoDiff.kt"
     ) { "Automatic differentiation" }
 }
+
+// Testing multi-receiver!
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile> {
+    enabled = false
+}

kmath-core/src/commonMain/kotlin/space/kscience/kmath/expressions/FunctionalExpressionAlgebra.kt

@@ -51,8 +51,8 @@ public open class FunctionalExpressionGroup<T, out A : Group<T>>(
 ) : FunctionalExpressionAlgebra<T, A>(algebra), Group<Expression<T>> {
     override val zero: Expression<T> get() = const(algebra.zero)
 
-    override fun Expression<T>.unaryMinus(): Expression<T> =
+    override fun negate(arg: Expression<T>): Expression<T> =
-        unaryOperation(GroupOps.MINUS_OPERATION, this)
+        unaryOperation(GroupOps.MINUS_OPERATION, arg)
 
     /**
      * Builds an Expression of addition of two another expressions.
@@ -60,26 +60,25 @@ public open class FunctionalExpressionGroup<T, out A : Group<T>>(
     override fun add(left: Expression<T>, right: Expression<T>): Expression<T> =
         binaryOperation(GroupOps.PLUS_OPERATION, left, right)
 
-//    /**
-//     * Builds an Expression of multiplication of expression by number.
-//     */
-//    override fun multiply(a: Expression<T>, k: Number): Expression<T> = Expression { arguments ->
-//        algebra.multiply(a.invoke(arguments), k)
-//    }
-
-    public operator fun Expression<T>.plus(arg: T): Expression<T> = this + const(arg)
-    public operator fun Expression<T>.minus(arg: T): Expression<T> = this - const(arg)
-    public operator fun T.plus(arg: Expression<T>): Expression<T> = arg + this
-    public operator fun T.minus(arg: Expression<T>): Expression<T> = arg - this
-
     override fun unaryOperationFunction(operation: String): (arg: Expression<T>) -> Expression<T> =
         super<FunctionalExpressionAlgebra>.unaryOperationFunction(operation)
 
     override fun binaryOperationFunction(operation: String): (left: Expression<T>, right: Expression<T>) -> Expression<T> =
         super<FunctionalExpressionAlgebra>.binaryOperationFunction(operation)
-
 }
 
+context(FunctionalExpressionGroup<T, A>)
+public operator fun <T, A : Group<T>> Expression<T>.plus(arg: T): Expression<T> = this + const(arg)
+
+context(FunctionalExpressionGroup<T, A>)
+public operator fun <T, A : Group<T>> Expression<T>.minus(arg: T): Expression<T> = this - const(arg)
+
+context(FunctionalExpressionGroup<T, A>)
+public operator fun <T, A : Group<T>> T.plus(arg: Expression<T>): Expression<T> = arg + this
+
+context(FunctionalExpressionGroup<T, A>)
+public operator fun <T, A : Group<T>> T.minus(arg: Expression<T>): Expression<T> = arg - this
+
 public open class FunctionalExpressionRing<T, out A : Ring<T>>(
     algebra: A,
 ) : FunctionalExpressionGroup<T, A>(algebra), Ring<Expression<T>> {
@@ -91,9 +90,6 @@ public open class FunctionalExpressionRing<T, out A : Ring<T>>(
     override fun multiply(left: Expression<T>, right: Expression<T>): Expression<T> =
         binaryOperationFunction(RingOps.TIMES_OPERATION)(left, right)
 
-    public operator fun Expression<T>.times(arg: T): Expression<T> = this * const(arg)
-    public operator fun T.times(arg: Expression<T>): Expression<T> = arg * this
-
     override fun unaryOperationFunction(operation: String): (arg: Expression<T>) -> Expression<T> =
         super<FunctionalExpressionGroup>.unaryOperationFunction(operation)
 
@@ -101,6 +97,12 @@ public open class FunctionalExpressionRing<T, out A : Ring<T>>(
         super<FunctionalExpressionGroup>.binaryOperationFunction(operation)
 }
 
+context(FunctionalExpressionRing<T, A>)
+public operator fun <T, A : Ring<T>> Expression<T>.times(arg: T): Expression<T> = this * const(arg)
+
+context(FunctionalExpressionRing<T, A>)
+public operator fun <T, A : Ring<T>> T.times(arg: Expression<T>): Expression<T> = arg * this
+
 public open class FunctionalExpressionField<T, out A : Field<T>>(
     algebra: A,
 ) : FunctionalExpressionRing<T, A>(algebra), Field<Expression<T>>, ScaleOperations<Expression<T>> {
@@ -110,9 +112,6 @@ public open class FunctionalExpressionField<T, out A : Field<T>>(
     override fun divide(left: Expression<T>, right: Expression<T>): Expression<T> =
         binaryOperationFunction(FieldOps.DIV_OPERATION)(left, right)
 
-    public operator fun Expression<T>.div(arg: T): Expression<T> = this / const(arg)
-    public operator fun T.div(arg: Expression<T>): Expression<T> = arg / this
-
     override fun unaryOperationFunction(operation: String): (arg: Expression<T>) -> Expression<T> =
         super<FunctionalExpressionRing>.unaryOperationFunction(operation)
 
@@ -127,6 +126,12 @@ public open class FunctionalExpressionField<T, out A : Field<T>>(
         super<FunctionalExpressionRing>.bindSymbolOrNull(value)
 }
 
+context(FunctionalExpressionField<T, A>)
+public operator fun <T, A : Field<T>> Expression<T>.div(arg: T): Expression<T> = this / const(arg)
+
+context(FunctionalExpressionField<T, A>)
+public operator fun <T, A : Field<T>> T.div(arg: Expression<T>): Expression<T> = arg / this
+
 public open class FunctionalExpressionExtendedField<T, out A : ExtendedField<T>>(
     algebra: A,
 ) : FunctionalExpressionField<T, A>(algebra), ExtendedField<Expression<T>> {

kmath-core/src/commonMain/kotlin/space/kscience/kmath/expressions/MstAlgebra.kt

@@ -32,14 +32,12 @@ public object MstGroup : Group<MST>, NumericAlgebra<MST>, ScaleOperations<MST> {
     override fun number(value: Number): MST.Numeric = MstNumericAlgebra.number(value)
     override fun bindSymbolOrNull(value: String): Symbol = MstNumericAlgebra.bindSymbolOrNull(value)
     override fun add(left: MST, right: MST): MST.Binary = binaryOperationFunction(GroupOps.PLUS_OPERATION)(left, right)
-    override operator fun MST.unaryPlus(): MST.Unary =
-        unaryOperationFunction(GroupOps.PLUS_OPERATION)(this)
 
-    override operator fun MST.unaryMinus(): MST.Unary =
+    override fun negate(arg: MST): MST.Unary =
-        unaryOperationFunction(GroupOps.MINUS_OPERATION)(this)
+        unaryOperationFunction(GroupOps.MINUS_OPERATION)(arg)
 
-    override operator fun MST.minus(arg: MST): MST.Binary =
+    override fun subtract(left: MST, right: MST): MST.Binary =
-        binaryOperationFunction(GroupOps.MINUS_OPERATION)(this, arg)
+        binaryOperationFunction(GroupOps.MINUS_OPERATION)(left, right)
 
     override fun scale(a: MST, value: Double): MST.Binary =
         binaryOperationFunction(RingOps.TIMES_OPERATION)(a, number(value))
@@ -70,9 +68,8 @@ public object MstRing : Ring<MST>, NumbersAddOps<MST>, ScaleOperations<MST> {
     override fun multiply(left: MST, right: MST): MST.Binary =
         binaryOperationFunction(RingOps.TIMES_OPERATION)(left, right)
 
-    override operator fun MST.unaryPlus(): MST.Unary = MstGroup { +this@unaryPlus }
+    override fun negate(arg: MST): MST.Unary = MstGroup.negate(arg)
-    override operator fun MST.unaryMinus(): MST.Unary = MstGroup { -this@unaryMinus }
+    override fun subtract(left: MST, right: MST): MST.Binary = MstGroup.subtract(left, right)
-    override operator fun MST.minus(arg: MST): MST.Binary = MstGroup { this@minus - arg }
 
     override fun binaryOperationFunction(operation: String): (left: MST, right: MST) -> MST.Binary =
         MstGroup.binaryOperationFunction(operation)
@@ -101,9 +98,8 @@ public object MstField : Field<MST>, NumbersAddOps<MST>, ScaleOperations<MST> {
     override fun divide(left: MST, right: MST): MST.Binary =
         binaryOperationFunction(FieldOps.DIV_OPERATION)(left, right)
 
-    override operator fun MST.unaryPlus(): MST.Unary = MstRing { +this@unaryPlus }
+    override fun negate(arg: MST): MST.Unary = MstRing.negate(arg)
-    override operator fun MST.unaryMinus(): MST.Unary = MstRing { -this@unaryMinus }
+    override fun subtract(left: MST, right: MST): MST.Binary = MstRing.subtract(left, right)
-    override operator fun MST.minus(arg: MST): MST.Binary = MstRing { this@minus - arg }
 
     override fun binaryOperationFunction(operation: String): (left: MST, right: MST) -> MST.Binary =
         MstRing.binaryOperationFunction(operation)
@@ -142,9 +138,8 @@ public object MstExtendedField : ExtendedField<MST>, NumericAlgebra<MST> {
 
     override fun multiply(left: MST, right: MST): MST.Binary = MstField.multiply(left, right)
     override fun divide(left: MST, right: MST): MST.Binary = MstField.divide(left, right)
-    override operator fun MST.unaryPlus(): MST.Unary = MstField { +this@unaryPlus }
+    override fun negate(arg: MST): MST.Unary = MstField.negate(arg)
-    override operator fun MST.unaryMinus(): MST.Unary = MstField { -this@unaryMinus }
+    override fun subtract(left: MST, right: MST): MST.Binary = MstField.subtract(left, right)
-    override operator fun MST.minus(arg: MST): MST.Binary = MstField { this@minus - arg }
 
     override fun power(arg: MST, pow: Number): MST.Binary =
         binaryOperationFunction(PowerOperations.POW_OPERATION)(arg, number(pow))

kmath-core/src/commonMain/kotlin/space/kscience/kmath/expressions/SimpleAutoDiff.kt

@@ -163,8 +163,8 @@ public open class SimpleAutoDiffField<T : Any, F : Field<T>>(
 //        derive(const { this@minus.value - one * b.toDouble() }) { z -> d += z.d }
 
 
-    override fun AutoDiffValue<T>.unaryMinus(): AutoDiffValue<T> =
+    override fun negate(arg: AutoDiffValue<T>): AutoDiffValue<T> =
-        derive(const { -value }) { z -> d -= z.d }
+        derive(const { -arg.value }) { z -> arg.d -= z.d }
 
     // Basic math (+, -, *, /)
 

kmath-core/src/commonMain/kotlin/space/kscience/kmath/expressions/specialExpressions.kt

@@ -5,8 +5,7 @@
 
 package space.kscience.kmath.expressions
 
-import space.kscience.kmath.operations.ExtendedField
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.asIterable
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.indices
 import kotlin.jvm.JvmName

kmath-core/src/commonMain/kotlin/space/kscience/kmath/linear/DoubleLinearSpace.kt

@@ -9,9 +9,7 @@ import space.kscience.kmath.misc.PerformancePitfall
 import space.kscience.kmath.nd.DoubleFieldOpsND
 import space.kscience.kmath.nd.as2D
 import space.kscience.kmath.nd.asND
-import space.kscience.kmath.operations.DoubleBufferOps
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.DoubleField
-import space.kscience.kmath.operations.invoke
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.DoubleBuffer
 

kmath-core/src/commonMain/kotlin/space/kscience/kmath/linear/LinearSpace.kt

@@ -10,10 +10,7 @@ import space.kscience.kmath.nd.MutableStructure2D
 import space.kscience.kmath.nd.Structure2D
 import space.kscience.kmath.nd.StructureFeature
 import space.kscience.kmath.nd.as1D
-import space.kscience.kmath.operations.BufferRingOps
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.DoubleField
-import space.kscience.kmath.operations.Ring
-import space.kscience.kmath.operations.invoke
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.BufferFactory
 import space.kscience.kmath.structures.DoubleBuffer

kmath-core/src/commonMain/kotlin/space/kscience/kmath/linear/MatrixWrapper.kt

@@ -89,6 +89,5 @@ public class TransposedFeature<out T : Any>(public val original: Matrix<T>) : Ma
  * Create a virtual transposed matrix without copying anything. `A.transpose().transpose() === A`
  */
 @Suppress("UNCHECKED_CAST")
-@OptIn(UnstableKMathAPI::class)
 public fun <T : Any> Matrix<T>.transpose(): Matrix<T> = getFeature(TransposedFeature::class)?.original as? Matrix<T>
     ?: VirtualMatrix(colNum, rowNum) { i, j -> get(j, i) }.withFeature(TransposedFeature(this))

kmath-core/src/commonMain/kotlin/space/kscience/kmath/misc/cumulative.kt

@@ -7,6 +7,7 @@ package space.kscience.kmath.misc
 
 import space.kscience.kmath.operations.Ring
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.plus
 import kotlin.jvm.JvmName
 
 /**

kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/AlgebraND.kt

@@ -127,50 +127,53 @@ public interface GroupOpsND<T, out A : GroupOps<T>> : GroupOps<StructureND<T>>,
     override fun add(left: StructureND<T>, right: StructureND<T>): StructureND<T> =
         zip(left, right) { aValue, bValue -> add(aValue, bValue) }
 
-    // TODO move to extensions after KEEP-176
+    public companion object
+}
 
-    /**
+/**
  * Adds an ND structure to an element of it.
  *
  * @receiver the augend.
  * @param arg the addend.
  * @return the sum.
  */
-    @OptIn(PerformancePitfall::class)
+context(GroupOpsND<T, A>)
-    public operator fun StructureND<T>.plus(arg: T): StructureND<T> = this.map { value -> add(arg, value) }
+@OptIn(PerformancePitfall::class)
+public operator fun <T, A : GroupOps<T>> StructureND<T>.plus(arg: T): StructureND<T> = this.map { value -> add(arg, value) }
 
-    /**
+/**
  * Subtracts an element from ND structure of it.
  *
  * @receiver the dividend.
  * @param arg the divisor.
  * @return the quotient.
  */
-    @OptIn(PerformancePitfall::class)
+context(GroupOpsND<T, A>)
-    public operator fun StructureND<T>.minus(arg: T): StructureND<T> = this.map { value -> add(arg, -value) }
+@OptIn(PerformancePitfall::class)
+public operator fun <T, A : GroupOps<T>> StructureND<T>.minus(arg: T): StructureND<T> = this.map { value -> add(arg, -value) }
 
-    /**
+/**
  * Adds an element to ND structure of it.
  *
  * @receiver the augend.
  * @param arg the addend.
  * @return the sum.
  */
-    @OptIn(PerformancePitfall::class)
+context(GroupOpsND<T, A>)
-    public operator fun T.plus(arg: StructureND<T>): StructureND<T> = arg.map { value -> add(this@plus, value) }
+@OptIn(PerformancePitfall::class)
+public operator fun <T, A : GroupOps<T>> T.plus(arg: StructureND<T>): StructureND<T> = arg.map { value -> add(this@plus, value) }
 
-    /**
+/**
  * Subtracts an ND structure from an element of it.
  *
  * @receiver the dividend.
  * @param arg the divisor.
  * @return the quotient.
  */
-    @OptIn(PerformancePitfall::class)
+context(GroupOpsND<T, A>)
-    public operator fun T.minus(arg: StructureND<T>): StructureND<T> = arg.map { value -> add(-this@minus, value) }
+@OptIn(PerformancePitfall::class)
+public operator fun <T, A : GroupOps<T>> T.minus(arg: StructureND<T>): StructureND<T> = arg.map { value -> add(-this@minus, value) }
 
-    public companion object
-}
 
 public interface GroupND<T, out A : Group<T>> : Group<StructureND<T>>, GroupOpsND<T, A>, WithShape {
     override val zero: StructureND<T> get() = structureND(shape) { elementAlgebra.zero }
@@ -194,30 +197,33 @@ public interface RingOpsND<T, out A : RingOps<T>> : RingOps<StructureND<T>>, Gro
     override fun multiply(left: StructureND<T>, right: StructureND<T>): StructureND<T> =
         zip(left, right) { aValue, bValue -> multiply(aValue, bValue) }
 
-    //TODO move to extensions with context receivers
 
-    /**
+    public companion object
+}
+
+/**
  * Multiplies an ND structure by an element of it.
  *
  * @receiver the multiplicand.
  * @param arg the multiplier.
  * @return the product.
  */
-    @OptIn(PerformancePitfall::class)
+context(RingOpsND<T, A>)
-    public operator fun StructureND<T>.times(arg: T): StructureND<T> = this.map { value -> multiply(arg, value) }
+@OptIn(PerformancePitfall::class)
+public operator fun <T, A : RingOps<T>> StructureND<T>.times(arg: T): StructureND<T> =
+    this.map { value -> multiply(arg, value) }
 
-    /**
+/**
  * Multiplies an element by a ND structure of it.
  *
  * @receiver the multiplicand.
  * @param arg the multiplier.
  * @return the product.
  */
-    @OptIn(PerformancePitfall::class)
+context(RingOpsND<T, A>)
-    public operator fun T.times(arg: StructureND<T>): StructureND<T> = arg.map { value -> multiply(this@times, value) }
+@OptIn(PerformancePitfall::class)
-
+public operator fun <T, A : RingOps<T>> T.times(arg: StructureND<T>): StructureND<T> =
-    public companion object
+    arg.map { value -> multiply(this@times, value) }
-}
 
 public interface RingND<T, out A : Ring<T>> : Ring<StructureND<T>>, RingOpsND<T, A>, GroupND<T, A>, WithShape {
     override val one: StructureND<T> get() = structureND(shape) { elementAlgebra.one }
@@ -245,30 +251,32 @@ public interface FieldOpsND<T, out A : Field<T>> :
     override fun divide(left: StructureND<T>, right: StructureND<T>): StructureND<T> =
         zip(left, right) { aValue, bValue -> divide(aValue, bValue) }
 
-    //TODO move to extensions after https://github.com/Kotlin/KEEP/blob/master/proposals/context-receivers.md
+    @OptIn(PerformancePitfall::class)
-    /**
+    override fun scale(a: StructureND<T>, value: Double): StructureND<T> = a.map { scale(it, value) }
+}
+
+/**
  * Divides an ND structure by an element of it.
  *
  * @receiver the dividend.
  * @param arg the divisor.
  * @return the quotient.
  */
-    @OptIn(PerformancePitfall::class)
+context(FieldOpsND<T, A>)
-    public operator fun StructureND<T>.div(arg: T): StructureND<T> = this.map { value -> divide(arg, value) }
+@OptIn(PerformancePitfall::class)
+public operator fun <T, A : Field<T>> StructureND<T>.div(arg: T): StructureND<T> = this.map { value -> divide(arg, value) }
 
-    /**
+/**
  * Divides an element by an ND structure of it.
  *
  * @receiver the dividend.
  * @param arg the divisor.
  * @return the quotient.
  */
-    @OptIn(PerformancePitfall::class)
+context(FieldOpsND<T, A>)
-    public operator fun T.div(arg: StructureND<T>): StructureND<T> = arg.map { divide(it, this@div) }
+@OptIn(PerformancePitfall::class)
+public operator fun <T, A : Field<T>> T.div(arg: StructureND<T>): StructureND<T> = arg.map { divide(it, this@div) }
 
-    @OptIn(PerformancePitfall::class)
-    override fun scale(a: StructureND<T>, value: Double): StructureND<T> = a.map { scale(it, value) }
-}
 
 public interface FieldND<T, out A : Field<T>> : Field<StructureND<T>>, FieldOpsND<T, A>, RingND<T, A>, WithShape {
     override val one: StructureND<T> get() = structureND(shape) { elementAlgebra.one }

kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/BufferAlgebraND.kt

@@ -101,7 +101,7 @@ public open class BufferedGroupNDOps<T, out A : Group<T>>(
     override val bufferAlgebra: BufferAlgebra<T, A>,
     override val indexerBuilder: (IntArray) -> ShapeIndexer = BufferAlgebraND.defaultIndexerBuilder,
 ) : GroupOpsND<T, A>, BufferAlgebraND<T, A> {
-    override fun StructureND<T>.unaryMinus(): StructureND<T> = map { -it }
+    override fun negate(arg: StructureND<T>): StructureND<T> = arg.map { -it }
 }
 
 public open class BufferedRingOpsND<T, out A : Ring<T>>(

kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/DoubleFieldND.kt

@@ -76,50 +76,17 @@ public sealed class DoubleFieldOpsND : BufferedFieldOpsND<Double, DoubleField>(D
     override fun add(left: StructureND<Double>, right: StructureND<Double>): DoubleBufferND =
         zipInline(left.toBufferND(), right.toBufferND()) { l, r -> l + r }
 
+    override fun negate(arg: StructureND<Double>): DoubleBufferND = mapInline(arg.toBufferND()) { -it }
+
+    override fun subtract(left: StructureND<Double>, right: StructureND<Double>): DoubleBufferND =
+        zipInline(left.toBufferND(), right.toBufferND()) { l: Double, r: Double -> l - r }
+
     override fun multiply(left: StructureND<Double>, right: StructureND<Double>): DoubleBufferND =
         zipInline(left.toBufferND(), right.toBufferND()) { l, r -> l * r }
 
-    override fun StructureND<Double>.unaryMinus(): DoubleBufferND = mapInline(toBufferND()) { -it }
-
-    override fun StructureND<Double>.div(arg: StructureND<Double>): DoubleBufferND =
-        zipInline(toBufferND(), arg.toBufferND()) { l, r -> l / r }
-
     override fun divide(left: StructureND<Double>, right: StructureND<Double>): DoubleBufferND =
         zipInline(left.toBufferND(), right.toBufferND()) { l: Double, r: Double -> l / r }
 
-    override fun StructureND<Double>.div(arg: Double): DoubleBufferND =
-        mapInline(toBufferND()) { it / arg }
-
-    override fun Double.div(arg: StructureND<Double>): DoubleBufferND =
-        mapInline(arg.toBufferND()) { this / it }
-
-    override fun StructureND<Double>.unaryPlus(): DoubleBufferND = toBufferND()
-
-    override fun StructureND<Double>.plus(arg: StructureND<Double>): DoubleBufferND =
-        zipInline(toBufferND(), arg.toBufferND()) { l: Double, r: Double -> l + r }
-
-    override fun StructureND<Double>.minus(arg: StructureND<Double>): DoubleBufferND =
-        zipInline(toBufferND(), arg.toBufferND()) { l: Double, r: Double -> l - r }
-
-    override fun StructureND<Double>.times(arg: StructureND<Double>): DoubleBufferND =
-        zipInline(toBufferND(), arg.toBufferND()) { l: Double, r: Double -> l * r }
-
-    override fun StructureND<Double>.times(k: Number): DoubleBufferND =
-        mapInline(toBufferND()) { it * k.toDouble() }
-
-    override fun StructureND<Double>.div(k: Number): DoubleBufferND =
-        mapInline(toBufferND()) { it / k.toDouble() }
-
-    override fun Number.times(arg: StructureND<Double>): DoubleBufferND = arg * this
-
-    override fun StructureND<Double>.plus(arg: Double): DoubleBufferND = mapInline(toBufferND()) { it + arg }
-
-    override fun StructureND<Double>.minus(arg: Double): StructureND<Double> = mapInline(toBufferND()) { it - arg }
-
-    override fun Double.plus(arg: StructureND<Double>): StructureND<Double> = arg + this
-
-    override fun Double.minus(arg: StructureND<Double>): StructureND<Double> = mapInline(arg.toBufferND()) { this - it }
-
     override fun scale(a: StructureND<Double>, value: Double): DoubleBufferND =
         mapInline(a.toBufferND()) { it * value }
 
@@ -181,7 +148,7 @@ public class DoubleFieldND(override val shape: Shape) :
         it.kpow(pow)
     }
 
-    override fun power(arg: StructureND<Double>, pow: Number): DoubleBufferND = if(pow.isInteger()){
+    override fun power(arg: StructureND<Double>, pow: Number): DoubleBufferND = if (pow.isInteger()) {
         power(arg, pow.toInt())
     } else {
         val dpow = pow.toDouble()

kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/StructureND.kt

@@ -11,6 +11,7 @@ import space.kscience.kmath.misc.Featured
 import space.kscience.kmath.misc.PerformancePitfall
 import space.kscience.kmath.operations.Ring
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.minus
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.BufferFactory
 import kotlin.jvm.JvmName

kmath-core/src/commonMain/kotlin/space/kscience/kmath/operations/Algebra.kt

@@ -9,12 +9,6 @@ import space.kscience.kmath.expressions.Symbol
 import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.operations.Ring.Companion.optimizedPower
 
-/**
- * Stub for DSL the [Algebra] is.
- */
-@DslMarker
-public annotation class KMathContext
-
 /**
  * Represents an algebraic structure.
  *
@@ -137,46 +131,26 @@ public interface GroupOps<T> : Algebra<T> {
      */
     public fun add(left: T, right: T): T
 
-    // Operations to be performed in this context. Could be moved to extensions in case of KEEP-176.
-
     /**
      * The negation of this element.
      *
-     * @receiver this value.
+     * @param arg the element.
      * @return the additive inverse of this value.
      */
-    public operator fun T.unaryMinus(): T
+    public fun negate(arg: T): T
-
-    /**
-     * Returns this value.
-     *
-     * @receiver this value.
-     * @return this value.
-     */
-    public operator fun T.unaryPlus(): T = this
-
-    /**
-     * Addition of two elements.
-     *
-     * @receiver the augend.
-     * @param arg the addend.
-     * @return the sum.
-     */
-    public operator fun T.plus(arg: T): T = add(this, arg)
 
     /**
      * Subtraction of two elements.
      *
-     * @receiver the minuend.
+     * @parm left the minuend.
-     * @param arg the subtrahend.
+     * @param right the subtrahend.
      * @return the difference.
      */
-    public operator fun T.minus(arg: T): T = add(this, -arg)
+    public fun subtract(left: T, right: T): T = add(left, -right)
 
-    // Dynamic dispatch of operations
     override fun unaryOperationFunction(operation: String): (arg: T) -> T = when (operation) {
-        PLUS_OPERATION -> { arg -> +arg }
+        PLUS_OPERATION -> { arg -> arg }
-        MINUS_OPERATION -> { arg -> -arg }
+        MINUS_OPERATION -> ::negate
         else -> super.unaryOperationFunction(operation)
     }
 
@@ -199,6 +173,44 @@ public interface GroupOps<T> : Algebra<T> {
     }
 }
 
+/**
+ * The negation of this element.
+ *
+ * @receiver the element.
+ * @return the additive inverse of this value.
+ */
+context(GroupOps<T>)
+public operator fun <T> T.unaryMinus(): T = negate(this)
+
+/**
+ * Returns this value.
+ *
+ * @receiver this value.
+ * @return this value.
+ */
+context(GroupOps<T>)
+public operator fun <T> T.unaryPlus(): T = this
+
+/**
+ * Addition of two elements.
+ *
+ * @receiver the augend.
+ * @param arg the addend.
+ * @return the sum.
+ */
+context(GroupOps<T>)
+public operator fun <T> T.plus(arg: T): T = add(this, arg)
+
+/**
+ * Subtraction of two elements.
+ *
+ * @receiver the minuend.
+ * @param arg the subtrahend.
+ * @return the difference.
+ */
+context(GroupOps<T>)
+public operator fun <T> T.minus(arg: T): T = subtract(this, arg)
+
 /**
  * Represents group i.e., algebraic structure with associative, binary operation [add].
  *
@@ -226,14 +238,6 @@ public interface RingOps<T> : GroupOps<T> {
      */
     public fun multiply(left: T, right: T): T
 
-    /**
-     * Multiplies this element by scalar.
-     *
-     * @receiver the multiplier.
-     * @param arg the multiplicand.
-     */
-    public operator fun T.times(arg: T): T = multiply(this, arg)
-
     override fun binaryOperationFunction(operation: String): (left: T, right: T) -> T = when (operation) {
         TIMES_OPERATION -> ::multiply
         else -> super.binaryOperationFunction(operation)
@@ -247,6 +251,15 @@ public interface RingOps<T> : GroupOps<T> {
     }
 }
 
+/**
+ * Multiplies two elements.
+ *
+ * @receiver the multiplier.
+ * @param arg the multiplicand.
+ */
+context(RingOps<T>)
+public operator fun <T> T.times(arg: T): T = multiply(this, arg)
+
 /**
  * Represents ring i.e., algebraic structure with two associative binary operations called "addition" and
  * "multiplication" and their neutral elements.
@@ -264,7 +277,7 @@ public interface Ring<T> : Group<T>, RingOps<T> {
      */
     public fun power(arg: T, pow: UInt): T = optimizedPower(arg, pow)
 
-    public companion object{
+    public companion object {
         /**
          * Raises [arg] to the non-negative integer power [exponent].
          *
@@ -311,15 +324,6 @@ public interface FieldOps<T> : RingOps<T> {
      */
     public fun divide(left: T, right: T): T
 
-    /**
-     * Division of two elements.
-     *
-     * @receiver the dividend.
-     * @param arg the divisor.
-     * @return the quotient.
-     */
-    public operator fun T.div(arg: T): T = divide(this, arg)
-
     override fun binaryOperationFunction(operation: String): (left: T, right: T) -> T = when (operation) {
         DIV_OPERATION -> ::divide
         else -> super.binaryOperationFunction(operation)
@@ -333,6 +337,16 @@ public interface FieldOps<T> : RingOps<T> {
     }
 }
 
+/**
+ * Division of two elements.
+ *
+ * @receiver the dividend.
+ * @param arg the divisor.
+ * @return the quotient.
+ */
+context(FieldOps<T>)
+public operator fun <T> T.div(arg: T): T = divide(this, arg)
+
 /**
  * Represents field i.e., algebraic structure with three operations: associative, commutative addition and
  * multiplication, and division. **This interface differs from the eponymous mathematical definition: fields in KMath
@@ -345,7 +359,7 @@ public interface Field<T> : Ring<T>, FieldOps<T>, ScaleOperations<T>, NumericAlg
 
     public fun power(arg: T, pow: Int): T = optimizedPower(arg, pow)
 
-    public companion object{
+    public companion object {
         /**
          * Raises [arg] to the integer power [exponent].
          *
@@ -358,7 +372,10 @@ public interface Field<T> : Ring<T>, FieldOps<T>, ScaleOperations<T>, NumericAlg
          * @author Iaroslav Postovalov, Evgeniy Zhelenskiy
          */
         private fun <T> Field<T>.optimizedPower(arg: T, exponent: Int): T = when {
-            exponent < 0 -> one / (this as Ring<T>).optimizedPower(arg, if (exponent == Int.MIN_VALUE) Int.MAX_VALUE.toUInt().inc() else (-exponent).toUInt())
+            exponent < 0 -> one / (this as Ring<T>).optimizedPower(
+                arg,
+                if (exponent == Int.MIN_VALUE) Int.MAX_VALUE.toUInt().inc() else (-exponent).toUInt()
+            )
             else -> (this as Ring<T>).optimizedPower(arg, exponent.toUInt())
         }
     }

kmath-core/src/commonMain/kotlin/space/kscience/kmath/operations/BigInt.kt

@@ -33,7 +33,7 @@ public object BigIntField : Field<BigInt>, NumbersAddOps<BigInt>, ScaleOperation
     override fun number(value: Number): BigInt = value.toLong().toBigInt()
 
     @Suppress("EXTENSION_SHADOWED_BY_MEMBER")
-    override fun BigInt.unaryMinus(): BigInt = -this
+    override fun negate(arg: BigInt): BigInt = -arg
     override fun add(left: BigInt, right: BigInt): BigInt = left.plus(right)
     override fun scale(a: BigInt, value: Double): BigInt = a.times(number(value))
     override fun multiply(left: BigInt, right: BigInt): BigInt = left.times(right)

kmath-core/src/commonMain/kotlin/space/kscience/kmath/operations/BufferAlgebra.kt

@@ -137,7 +137,7 @@ public open class BufferRingOps<T, A: Ring<T>>(
 
     override fun add(left: Buffer<T>, right: Buffer<T>): Buffer<T> = zipInline(left, right) { l, r -> l + r }
     override fun multiply(left: Buffer<T>, right: Buffer<T>): Buffer<T> = zipInline(left, right) { l, r -> l * r }
-    override fun Buffer<T>.unaryMinus(): Buffer<T> = map { -it }
+    override fun negate(arg: Buffer<T>): Buffer<T> = arg.map { negate(it) }
 
     override fun unaryOperationFunction(operation: String): (arg: Buffer<T>) -> Buffer<T> =
         super<BufferAlgebra>.unaryOperationFunction(operation)
@@ -159,7 +159,7 @@ public open class BufferFieldOps<T, A : Field<T>>(
     override fun divide(left: Buffer<T>, right: Buffer<T>): Buffer<T> = zipInline(left, right) { l, r -> l / r }
 
     override fun scale(a: Buffer<T>, value: Double): Buffer<T> = a.map { scale(it, value) }
-    override fun Buffer<T>.unaryMinus(): Buffer<T> = map { -it }
+    override fun negate(arg: Buffer<T>): Buffer<T> = arg.map { -it }
 
     override fun binaryOperationFunction(operation: String): (left: Buffer<T>, right: Buffer<T>) -> Buffer<T> =
         super<BufferRingOps>.binaryOperationFunction(operation)

kmath-core/src/commonMain/kotlin/space/kscience/kmath/operations/DoubleBufferOps.kt

@@ -6,7 +6,6 @@
 package space.kscience.kmath.operations
 
 import space.kscience.kmath.linear.Point
-import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.BufferFactory
 import space.kscience.kmath.structures.DoubleBuffer
@@ -32,8 +31,6 @@ public abstract class DoubleBufferOps : BufferAlgebra<Double, DoubleField>, Exte
     override fun binaryOperationFunction(operation: String): (left: Buffer<Double>, right: Buffer<Double>) -> Buffer<Double> =
         super<ExtendedFieldOps>.binaryOperationFunction(operation)
 
-    override fun Buffer<Double>.unaryMinus(): DoubleBuffer = mapInline { -it }
-
     override fun add(left: Buffer<Double>, right: Buffer<Double>): DoubleBuffer {
         require(right.size == left.size) {
             "The size of the first buffer ${left.size} should be the same as for second one: ${right.size} "
@@ -46,18 +43,17 @@ public abstract class DoubleBufferOps : BufferAlgebra<Double, DoubleField>, Exte
         } else DoubleBuffer(DoubleArray(left.size) { left[it] + right[it] })
     }
 
-    override fun Buffer<Double>.plus(arg: Buffer<Double>): DoubleBuffer = add(this, arg)
+    override fun negate(arg: Buffer<Double>): DoubleBuffer = arg.mapInline { -it }
 
-    override fun Buffer<Double>.minus(arg: Buffer<Double>): DoubleBuffer {
+    override fun subtract(left: Buffer<Double>, right: Buffer<Double>): DoubleBuffer {
-        require(arg.size == this.size) {
+        require(left.size == right.size) {
-            "The size of the first buffer ${this.size} should be the same as for second one: ${arg.size} "
+            "The size of the first buffer ${left.size} should be the same as for second one: ${right.size} "
         }
 
-        return if (this is DoubleBuffer && arg is DoubleBuffer) {
+        return if (left is DoubleBuffer && right is DoubleBuffer)
-            val aArray = this.array
+            DoubleBuffer(DoubleArray(left.size) { left.array[it] - right.array[it] })
-            val bArray = arg.array
+        else
-            DoubleBuffer(DoubleArray(this.size) { aArray[it] - bArray[it] })
+            DoubleBuffer(DoubleArray(left.size) { left[it] - right[it] })
-        } else DoubleBuffer(DoubleArray(this.size) { this[it] - arg[it] })
     }
 
     //

kmath-core/src/commonMain/kotlin/space/kscience/kmath/operations/NumericAlgebra.kt

@@ -116,34 +116,38 @@ public interface ScaleOperations<T> : Algebra<T> {
      * @return the produce.
      */
     public fun scale(a: T, value: Double): T
+}
 
-    /**
+
+/**
  * Multiplication of this element by a scalar.
  *
  * @receiver the multiplier.
  * @param k the multiplicand.
  * @return the product.
  */
-    public operator fun T.times(k: Number): T = scale(this, k.toDouble())
+context(ScaleOperations<T>)
+public operator fun <T> T.times(k: Number): T = scale(this, k.toDouble())
 
-    /**
+/**
  * Division of this element by scalar.
  *
  * @receiver the dividend.
  * @param k the divisor.
  * @return the quotient.
  */
-    public operator fun T.div(k: Number): T = scale(this, 1.0 / k.toDouble())
+context(ScaleOperations<T>)
+public operator fun <T> T.div(k: Number): T = scale(this, 1.0 / k.toDouble())
 
-    /**
+/**
  * Multiplication of this number by element.
  *
  * @receiver the multiplier.
  * @param arg the multiplicand.
  * @return the product.
  */
-    public operator fun Number.times(arg: T): T = arg * this
+context(ScaleOperations<T>)
-}
+public operator fun <T> Number.times(arg: T): T = arg * this
 
 /**
  * A combination of [NumericAlgebra] and [Ring] that adds intrinsic simple operations on numbers like `T+1`

kmath-core/src/commonMain/kotlin/space/kscience/kmath/operations/numbers.kt

@@ -68,7 +68,7 @@ public object DoubleField : ExtendedField<Double>, Norm<Double, Double>, ScaleOp
     override inline val zero: Double get() = 0.0
     override inline val one: Double get() = 1.0
 
-    override inline fun number(value: Number): Double = value.toDouble()
+    override fun number(value: Number): Double = value.toDouble()
 
     override fun binaryOperationFunction(operation: String): (left: Double, right: Double) -> Double =
         when (operation) {
@@ -77,6 +77,8 @@ public object DoubleField : ExtendedField<Double>, Norm<Double, Double>, ScaleOp
         }
 
     override inline fun add(left: Double, right: Double): Double = left + right
+    override inline fun negate(arg: Double): Double = -arg
+    override inline fun subtract(left: Double, right: Double): Double = left - right
 
     override inline fun multiply(left: Double, right: Double): Double = left * right
     override inline fun divide(left: Double, right: Double): Double = left / right
@@ -108,12 +110,6 @@ public object DoubleField : ExtendedField<Double>, Norm<Double, Double>, ScaleOp
     override inline fun ln(arg: Double): Double = kotlin.math.ln(arg)
 
     override inline fun norm(arg: Double): Double = abs(arg)
-
-    override inline fun Double.unaryMinus(): Double = -this
-    override inline fun Double.plus(arg: Double): Double = this + arg
-    override inline fun Double.minus(arg: Double): Double = this - arg
-    override inline fun Double.times(arg: Double): Double = this * arg
-    override inline fun Double.div(arg: Double): Double = this / arg
 }
 
 public val Double.Companion.algebra: DoubleField get() = DoubleField
@@ -135,7 +131,10 @@ public object FloatField : ExtendedField<Float>, Norm<Float, Float> {
         }
 
     override inline fun add(left: Float, right: Float): Float = left + right
-    override fun scale(a: Float, value: Double): Float = a * value.toFloat()
+    override inline fun negate(arg: Float): Float = -arg
+    override inline fun subtract(left: Float, right: Float): Float = left - right
+
+    override inline fun scale(a: Float, value: Double): Float = a * value.toFloat()
 
     override inline fun multiply(left: Float, right: Float): Float = left * right
 
@@ -162,12 +161,6 @@ public object FloatField : ExtendedField<Float>, Norm<Float, Float> {
     override inline fun ln(arg: Float): Float = kotlin.math.ln(arg)
 
     override inline fun norm(arg: Float): Float = abs(arg)
-
-    override inline fun Float.unaryMinus(): Float = -this
-    override inline fun Float.plus(arg: Float): Float = this + arg
-    override inline fun Float.minus(arg: Float): Float = this - arg
-    override inline fun Float.times(arg: Float): Float = this * arg
-    override inline fun Float.div(arg: Float): Float = this / arg
 }
 
 public val Float.Companion.algebra: FloatField get() = FloatField
@@ -185,13 +178,11 @@ public object IntRing : Ring<Int>, Norm<Int, Int>, NumericAlgebra<Int> {
 
     override fun number(value: Number): Int = value.toInt()
     override inline fun add(left: Int, right: Int): Int = left + right
+    override inline fun negate(arg: Int): Int = -arg
+    override inline fun subtract(left: Int, right: Int): Int = left - right
+
     override inline fun multiply(left: Int, right: Int): Int = left * right
     override inline fun norm(arg: Int): Int = abs(arg)
-
-    override inline fun Int.unaryMinus(): Int = -this
-    override inline fun Int.plus(arg: Int): Int = this + arg
-    override inline fun Int.minus(arg: Int): Int = this - arg
-    override inline fun Int.times(arg: Int): Int = this * arg
 }
 
 public val Int.Companion.algebra: IntRing get() = IntRing
@@ -209,13 +200,11 @@ public object ShortRing : Ring<Short>, Norm<Short, Short>, NumericAlgebra<Short>
 
     override fun number(value: Number): Short = value.toShort()
     override inline fun add(left: Short, right: Short): Short = (left + right).toShort()
-    override inline fun multiply(left: Short, right: Short): Short = (left * right).toShort()
+    override inline fun negate(arg: Short): Short = (-arg).toShort()
-    override fun norm(arg: Short): Short = if (arg > 0) arg else (-arg).toShort()
+    override inline fun subtract(left: Short, right: Short): Short = (left - right).toShort()
 
-    override inline fun Short.unaryMinus(): Short = (-this).toShort()
+    override inline fun multiply(left: Short, right: Short): Short = (left * right).toShort()
-    override inline fun Short.plus(arg: Short): Short = (this + arg).toShort()
+    override inline fun norm(arg: Short): Short = if (arg > 0) arg else (-arg).toShort()
-    override inline fun Short.minus(arg: Short): Short = (this - arg).toShort()
-    override inline fun Short.times(arg: Short): Short = (this * arg).toShort()
 }
 
 public val Short.Companion.algebra: ShortRing get() = ShortRing
@@ -233,13 +222,12 @@ public object ByteRing : Ring<Byte>, Norm<Byte, Byte>, NumericAlgebra<Byte> {
 
     override fun number(value: Number): Byte = value.toByte()
     override inline fun add(left: Byte, right: Byte): Byte = (left + right).toByte()
-    override inline fun multiply(left: Byte, right: Byte): Byte = (left * right).toByte()
+    override inline fun negate(arg: Byte): Byte = (-arg).toByte()
-    override fun norm(arg: Byte): Byte = if (arg > 0) arg else (-arg).toByte()
+    override inline fun subtract(left: Byte, right: Byte): Byte = (left - right).toByte()
 
-    override inline fun Byte.unaryMinus(): Byte = (-this).toByte()
+    override inline fun multiply(left: Byte, right: Byte): Byte = (left * right).toByte()
-    override inline fun Byte.plus(arg: Byte): Byte = (this + arg).toByte()
+
-    override inline fun Byte.minus(arg: Byte): Byte = (this - arg).toByte()
+    override inline fun norm(arg: Byte): Byte = if (arg > 0) arg else (-arg).toByte()
-    override inline fun Byte.times(arg: Byte): Byte = (this * arg).toByte()
 }
 
 public val Byte.Companion.algebra: ByteRing get() = ByteRing
@@ -256,14 +244,13 @@ public object LongRing : Ring<Long>, Norm<Long, Long>, NumericAlgebra<Long> {
         get() = 1L
 
     override fun number(value: Number): Long = value.toLong()
-    override inline fun add(left: Long, right: Long): Long = left + right
-    override inline fun multiply(left: Long, right: Long): Long = left * right
-    override fun norm(arg: Long): Long = abs(arg)
 
-    override inline fun Long.unaryMinus(): Long = (-this)
+    override inline fun add(left: Long, right: Long): Long = left + right
-    override inline fun Long.plus(arg: Long): Long = (this + arg)
+    override inline fun negate(arg: Long): Long = -arg
-    override inline fun Long.minus(arg: Long): Long = (this - arg)
+    override inline fun subtract(left: Long, right: Long): Long = left - right
-    override inline fun Long.times(arg: Long): Long = (this * arg)
+
+    override inline fun multiply(left: Long, right: Long): Long = left * right
+    override inline fun norm(arg: Long): Long = abs(arg)
 }
 
 public val Long.Companion.algebra: LongRing get() = LongRing

kmath-core/src/commonTest/kotlin/space/kscience/kmath/expressions/ExpressionFieldTest.kt

@@ -6,6 +6,8 @@
 package space.kscience.kmath.expressions
 
 import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFails

kmath-core/src/commonTest/kotlin/space/kscience/kmath/expressions/InterpretTest.kt

@@ -7,13 +7,10 @@ package space.kscience.kmath.expressions
 
 import space.kscience.kmath.expressions.Symbol.Companion.x
 import space.kscience.kmath.misc.UnstableKMathAPI
-import space.kscience.kmath.operations.BooleanAlgebra
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.DoubleField
-import space.kscience.kmath.operations.invoke
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
-
 internal class InterpretTest {
     @Test
     fun interpretation() {

kmath-core/src/commonTest/kotlin/space/kscience/kmath/expressions/SimpleAutoDiffTest.kt

@@ -5,8 +5,7 @@
 
 package space.kscience.kmath.expressions
 
-import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.bindSymbol
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.asBuffer
 import kotlin.math.E

kmath-core/src/commonTest/kotlin/space/kscience/kmath/structures/NDFieldTest.kt

@@ -10,6 +10,7 @@ import space.kscience.kmath.nd.ndAlgebra
 import space.kscience.kmath.nd.structureND
 import space.kscience.kmath.operations.DoubleField
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.times
 import space.kscience.kmath.testutils.FieldVerifier
 import kotlin.test.Test
 import kotlin.test.assertEquals

kmath-core/src/commonTest/kotlin/space/kscience/kmath/structures/NumberNDFieldTest.kt

@@ -8,10 +8,7 @@ package space.kscience.kmath.structures
 import space.kscience.kmath.linear.linearSpace
 import space.kscience.kmath.misc.PerformancePitfall
 import space.kscience.kmath.nd.*
-import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.Norm
-import space.kscience.kmath.operations.algebra
-import space.kscience.kmath.operations.invoke
 import kotlin.math.abs
 import kotlin.math.pow
 import kotlin.test.Test

kmath-core/src/commonTest/kotlin/space/kscience/kmath/testutils/FieldVerifier.kt

@@ -5,8 +5,7 @@
 
 package space.kscience.kmath.testutils
 
-import space.kscience.kmath.operations.Field
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.invoke
 import kotlin.test.assertEquals
 import kotlin.test.assertNotEquals
 

kmath-core/src/commonTest/kotlin/space/kscience/kmath/testutils/RingVerifier.kt

@@ -5,9 +5,7 @@
 
 package space.kscience.kmath.testutils
 
-import space.kscience.kmath.operations.Ring
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.ScaleOperations
-import space.kscience.kmath.operations.invoke
 import kotlin.test.assertEquals
 
 internal open class RingVerifier<T, out A>(algebra: A, a: T, b: T, c: T, x: Number) :

kmath-core/src/commonTest/kotlin/space/kscience/kmath/testutils/SpaceVerifier.kt

@@ -5,9 +5,7 @@
 
 package space.kscience.kmath.testutils
 
-import space.kscience.kmath.operations.Ring
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.ScaleOperations
-import space.kscience.kmath.operations.invoke
 import kotlin.test.assertEquals
 import kotlin.test.assertNotEquals
 

kmath-core/src/jvmMain/kotlin/space/kscience/kmath/operations/BigNumbers.kt

@@ -19,10 +19,10 @@ public object JBigIntegerField : Ring<BigInteger>, NumericAlgebra<BigInteger> {
 
     override fun number(value: Number): BigInteger = BigInteger.valueOf(value.toLong())
     override fun add(left: BigInteger, right: BigInteger): BigInteger = left.add(right)
-    override operator fun BigInteger.minus(arg: BigInteger): BigInteger = subtract(arg)
+    override fun negate(arg: BigInteger): BigInteger = arg.negate()
-    override fun multiply(left: BigInteger, right: BigInteger): BigInteger = left.multiply(right)
+    override fun subtract(left: BigInteger, right: BigInteger): BigInteger = left.subtract(right)
 
-    override operator fun BigInteger.unaryMinus(): BigInteger = negate()
+    override fun multiply(left: BigInteger, right: BigInteger): BigInteger = left.multiply(right)
 }
 
 /**
@@ -40,7 +40,9 @@ public abstract class JBigDecimalFieldBase internal constructor(
         get() = BigDecimal.ONE
 
     override fun add(left: BigDecimal, right: BigDecimal): BigDecimal = left.add(right)
-    override operator fun BigDecimal.minus(arg: BigDecimal): BigDecimal = subtract(arg)
+    override fun negate(arg: BigDecimal): BigDecimal = arg.negate(mathContext)
+    override fun subtract(left: BigDecimal, right: BigDecimal): BigDecimal = left.subtract(right)
+
     override fun number(value: Number): BigDecimal = BigDecimal.valueOf(value.toDouble())
 
     override fun scale(a: BigDecimal, value: Double): BigDecimal =
@@ -50,7 +52,6 @@ public abstract class JBigDecimalFieldBase internal constructor(
     override fun divide(left: BigDecimal, right: BigDecimal): BigDecimal = left.divide(right, mathContext)
     override fun power(arg: BigDecimal, pow: Number): BigDecimal = arg.pow(pow.toInt(), mathContext)
     override fun sqrt(arg: BigDecimal): BigDecimal = arg.sqrt(mathContext)
-    override operator fun BigDecimal.unaryMinus(): BigDecimal = negate(mathContext)
 }
 
 /**

kmath-coroutines/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     kotlin("multiplatform")
     id("ru.mipt.npm.gradle.common")
-    id("ru.mipt.npm.gradle.native")
+//    id("ru.mipt.npm.gradle.native")
 }
 
 kotlin.sourceSets {
@@ -25,3 +25,8 @@ kotlin.sourceSets {
 readme {
     maturity = ru.mipt.npm.gradle.Maturity.EXPERIMENTAL
 }
+
+// Testing multi-receiver!
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile> {
+    enabled = false
+}

kmath-coroutines/src/commonMain/kotlin/space/kscience/kmath/chains/flowExtra.kt

@@ -10,10 +10,7 @@ import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.runningReduce
 import kotlinx.coroutines.flow.scan
-import space.kscience.kmath.operations.GroupOps
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.Ring
-import space.kscience.kmath.operations.ScaleOperations
-import space.kscience.kmath.operations.invoke
 
 public fun <T> Flow<T>.cumulativeSum(group: GroupOps<T>): Flow<T> =
     group { runningReduce { sum, element -> sum + element } }

kmath-coroutines/src/jvmMain/kotlin/space/kscience/kmath/structures/LazyStructureND.kt

@@ -39,15 +39,11 @@ public fun <T> StructureND<T>.deferred(index: IntArray): Deferred<T> =
 public suspend fun <T> StructureND<T>.await(index: IntArray): T =
     if (this is LazyStructureND<T>) await(index) else get(index)
 
-/**
+context(CoroutineScope)
- * PENDING would benefit from KEEP-176
- */
 public inline fun <T, R> StructureND<T>.mapAsyncIndexed(
-    scope: CoroutineScope,
     crossinline function: suspend (T, index: IntArray) -> R,
-): LazyStructureND<R> = LazyStructureND(scope, shape) { index -> function(get(index), index) }
+): LazyStructureND<R> = LazyStructureND(this@CoroutineScope, shape) { index -> function(get(index), index) }
 
-public inline fun <T, R> StructureND<T>.mapAsync(
+context(CoroutineScope)
-    scope: CoroutineScope,
+public inline fun <T, R> StructureND<T>.mapAsync(crossinline function: suspend (T) -> R): LazyStructureND<R> =
-    crossinline function: suspend (T) -> R,
+    LazyStructureND(this@CoroutineScope, shape) { index -> function(get(index)) }
-): LazyStructureND<R> = LazyStructureND(scope, shape) { index -> function(get(index)) }

kmath-dimensions/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     kotlin("multiplatform")
     id("ru.mipt.npm.gradle.common")
-    id("ru.mipt.npm.gradle.native")
+//    id("ru.mipt.npm.gradle.native")
 }
 
 description = "A proof of concept module for adding type-safe dimensions to structures"
@@ -23,3 +23,8 @@ kotlin.sourceSets {
 readme {
     maturity = ru.mipt.npm.gradle.Maturity.PROTOTYPE
 }
+
+// Testing multi-receiver!
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile> {
+    enabled = false
+}

kmath-ejml/build.gradle.kts

@@ -33,10 +33,19 @@ readme {
     ) { "LinearSpace implementations." }
 }
 
-kotlin.sourceSets.main {
+kotlin.sourceSets {
+    filter { it.name.contains("test", true) }
+        .map(org.jetbrains.kotlin.gradle.plugin.KotlinSourceSet::languageSettings)
+        .forEach {
+            it.optIn("space.kscience.kmath.misc.PerformancePitfall")
+            it.optIn("space.kscience.kmath.misc.UnstableKMathAPI")
+        }
+
+    main {
         val codegen by tasks.creating {
             ejmlCodegen(kotlin.srcDirs.first().absolutePath + "/space/kscience/kmath/ejml/_generated.kt")
         }
 
         kotlin.srcDirs(files().builtBy(codegen))
+    }
 }

kmath-ejml/src/main/kotlin/space/kscience/kmath/ejml/_generated.kt

@@ -208,7 +208,7 @@ public object EjmlLinearSpaceDDRM : EjmlLinearSpace<Double, DoubleField, DMatrix
         structure.getFeature(type)?.let { return it }
         val origin = structure.toEjml().origin
 
-        return when (type) {
+        return type.cast(when (type) {
             InverseMatrixFeature::class -> object : InverseMatrixFeature<Double> {
                 override val inverse: Matrix<Double> by lazy {
                     val res = origin.copy()
@@ -270,8 +270,8 @@ public object EjmlLinearSpaceDDRM : EjmlLinearSpace<Double, DoubleField, DMatrix
                 override val p: Matrix<Double> by lazy { lup.getRowPivot(null).wrapMatrix() }
             }
 
-            else -> null
+            else -> return null
-        }?.let(type::cast)
+        })
     }
 
     /**
@@ -442,7 +442,7 @@ public object EjmlLinearSpaceFDRM : EjmlLinearSpace<Float, FloatField, FMatrixRM
         structure.getFeature(type)?.let { return it }
         val origin = structure.toEjml().origin
 
-        return when (type) {
+        return type.cast(when (type) {
             InverseMatrixFeature::class -> object : InverseMatrixFeature<Float> {
                 override val inverse: Matrix<Float> by lazy {
                     val res = origin.copy()
@@ -504,8 +504,8 @@ public object EjmlLinearSpaceFDRM : EjmlLinearSpace<Float, FloatField, FMatrixRM
                 override val p: Matrix<Float> by lazy { lup.getRowPivot(null).wrapMatrix() }
             }
 
-            else -> null
+            else -> return null
-        }?.let(type::cast)
+        })
     }
 
     /**
@@ -684,7 +684,7 @@ public object EjmlLinearSpaceDSCC : EjmlLinearSpace<Double, DoubleField, DMatrix
         structure.getFeature(type)?.let { return it }
         val origin = structure.toEjml().origin
 
-        return when (type) {
+        return type.cast(when (type) {
             QRDecompositionFeature::class -> object : QRDecompositionFeature<Double> {
                 private val qr by lazy {
                     DecompositionFactory_DSCC.qr(FillReducing.NONE).apply { decompose(origin.copy()) }
@@ -733,8 +733,8 @@ public object EjmlLinearSpaceDSCC : EjmlLinearSpace<Double, DoubleField, DMatrix
                 override val determinant: Double by lazy { elementAlgebra.number(lu.computeDeterminant().real) }
             }
 
-            else -> null
+            else -> return null
-        }?.let(type::cast)
+        })
     }
 
     /**
@@ -913,7 +913,7 @@ public object EjmlLinearSpaceFSCC : EjmlLinearSpace<Float, FloatField, FMatrixSp
         structure.getFeature(type)?.let { return it }
         val origin = structure.toEjml().origin
 
-        return when (type) {
+        return type.cast(when (type) {
             QRDecompositionFeature::class -> object : QRDecompositionFeature<Float> {
                 private val qr by lazy {
                     DecompositionFactory_FSCC.qr(FillReducing.NONE).apply { decompose(origin.copy()) }
@@ -962,8 +962,8 @@ public object EjmlLinearSpaceFSCC : EjmlLinearSpace<Float, FloatField, FMatrixSp
                 override val determinant: Float by lazy { elementAlgebra.number(lu.computeDeterminant().real) }
             }
 
-            else -> null
+            else -> return null
-        }?.let(type::cast)
+        })
     }
 
     /**

kmath-for-real/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     kotlin("multiplatform")
     id("ru.mipt.npm.gradle.common")
-    id("ru.mipt.npm.gradle.native")
+//    id("ru.mipt.npm.gradle.native")
 }
 
 kotlin.sourceSets.commonMain {
@@ -40,3 +40,8 @@ readme {
         "Uniform grid generators"
     }
 }
+
+// Testing multi-receiver!
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile> {
+    enabled = false
+}

kmath-functions/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     kotlin("multiplatform")
     id("ru.mipt.npm.gradle.common")
-    id("ru.mipt.npm.gradle.native")
+//    id("ru.mipt.npm.gradle.native")
 }
 
 description = "Functions, integration and interpolation"
@@ -32,3 +32,8 @@ readme {
         "Univariate and multivariate quadratures"
     }
 }
+
+// Testing multi-receiver!
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile> {
+    enabled = false
+}

kmath-functions/src/commonMain/kotlin/space/kscience/kmath/functions/Polynomial.kt

@@ -71,7 +71,7 @@ public fun <T, A> Polynomial<T>.integrate(
 ): Polynomial<T> where  A : Field<T>, A : NumericAlgebra<T> = algebra {
     val integratedCoefficients = buildList(coefficients.size + 1) {
         add(zero)
-        coefficients.forEachIndexed{ index, t -> add(t / (number(index) + one)) }
+        coefficients.forEachIndexed { index, t -> add(t / (number(index) + one)) }
     }
     Polynomial(integratedCoefficients)
 }
@@ -100,8 +100,8 @@ public class PolynomialSpace<T, C>(
 ) : Group<Polynomial<T>>, ScaleOperations<Polynomial<T>> where C : Ring<T>, C : ScaleOperations<T> {
     override val zero: Polynomial<T> = Polynomial(emptyList())
 
-    override fun Polynomial<T>.unaryMinus(): Polynomial<T> = ring {
+    override fun negate(arg: Polynomial<T>): Polynomial<T> = ring {
-        Polynomial(coefficients.map { -it })
+        Polynomial(arg.coefficients.map { -it })
     }
 
     override fun add(left: Polynomial<T>, right: Polynomial<T>): Polynomial<T> {

kmath-functions/src/commonMain/kotlin/space/kscience/kmath/integration/GaussIntegrator.kt

@@ -6,6 +6,9 @@ package space.kscience.kmath.integration
 
 import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.operations.Field
+import space.kscience.kmath.operations.minus
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.asBuffer
 import space.kscience.kmath.structures.indices

kmath-functions/src/commonMain/kotlin/space/kscience/kmath/integration/SimpsonIntegrator.kt

@@ -6,10 +6,7 @@
 package space.kscience.kmath.integration
 
 import space.kscience.kmath.misc.UnstableKMathAPI
-import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.Field
-import space.kscience.kmath.operations.invoke
-import space.kscience.kmath.operations.sum
 
 /**
  * Use double pass Simpson rule integration with a fixed number of points.
@@ -60,7 +57,8 @@ public class SimpsonIntegrator<T : Any>(
 }
 
 @UnstableKMathAPI
-public val <T : Any> Field<T>.simpsonIntegrator: SimpsonIntegrator<T> get() = SimpsonIntegrator(this)
+public val <T : Any> Field<T>.simpsonIntegrator: SimpsonIntegrator<T>
+    get() = SimpsonIntegrator(this)
 
 /**
  * Use double pass Simpson rule integration with a fixed number of points.

kmath-functions/src/commonMain/kotlin/space/kscience/kmath/interpolation/LinearInterpolator.kt

@@ -9,8 +9,7 @@ import space.kscience.kmath.data.XYColumnarData
 import space.kscience.kmath.functions.PiecewisePolynomial
 import space.kscience.kmath.functions.Polynomial
 import space.kscience.kmath.misc.UnstableKMathAPI
-import space.kscience.kmath.operations.Field
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.invoke
 
 @OptIn(UnstableKMathAPI::class)
 internal fun <T : Comparable<T>> insureSorted(points: XYColumnarData<*, T, *>) {

kmath-functions/src/commonMain/kotlin/space/kscience/kmath/interpolation/SplineInterpolator.kt

@@ -9,9 +9,7 @@ import space.kscience.kmath.data.XYColumnarData
 import space.kscience.kmath.functions.PiecewisePolynomial
 import space.kscience.kmath.functions.Polynomial
 import space.kscience.kmath.misc.UnstableKMathAPI
-import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.Field
-import space.kscience.kmath.operations.invoke
 import space.kscience.kmath.structures.DoubleBuffer
 import space.kscience.kmath.structures.MutableBufferFactory
 

kmath-geometry/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     kotlin("multiplatform")
     id("ru.mipt.npm.gradle.common")
-    id("ru.mipt.npm.gradle.native")
+//    id("ru.mipt.npm.gradle.native")
 }
 
 kotlin.sourceSets.commonMain {
@@ -13,3 +13,8 @@ kotlin.sourceSets.commonMain {
 readme {
     maturity = ru.mipt.npm.gradle.Maturity.PROTOTYPE
 }
+
+// Testing multi-receiver!
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile> {
+    enabled = false
+}

kmath-geometry/src/commonMain/kotlin/space/kscience/kmath/geometry/Euclidean2DSpace.kt

@@ -6,12 +6,11 @@
 package space.kscience.kmath.geometry
 
 import space.kscience.kmath.linear.Point
-import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.operations.ScaleOperations
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.minus
 import kotlin.math.sqrt
 
-@OptIn(UnstableKMathAPI::class)
 public interface Vector2D : Point<Double>, Vector {
     public val x: Double
     public val y: Double
@@ -44,7 +43,7 @@ public object Euclidean2DSpace : GeometrySpace<Vector2D>, ScaleOperations<Vector
     override val zero: Vector2D by lazy { Vector2D(0.0, 0.0) }
 
     public fun Vector2D.norm(): Double = sqrt(x * x + y * y)
-    override fun Vector2D.unaryMinus(): Vector2D = Vector2D(-x, -y)
+    override fun negate(arg: Vector2D): Vector2D = Vector2D(-arg.x, -arg.y)
 
     override fun Vector2D.distanceTo(other: Vector2D): Double = (this - other).norm()
     override fun add(left: Vector2D, right: Vector2D): Vector2D = Vector2D(left.x + right.x, left.y + right.y)

kmath-geometry/src/commonMain/kotlin/space/kscience/kmath/geometry/Euclidean3DSpace.kt

@@ -6,12 +6,11 @@
 package space.kscience.kmath.geometry
 
 import space.kscience.kmath.linear.Point
-import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.operations.ScaleOperations
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.minus
 import kotlin.math.sqrt
 
-@OptIn(UnstableKMathAPI::class)
 public interface Vector3D : Point<Double>, Vector {
     public val x: Double
     public val y: Double
@@ -43,7 +42,7 @@ public object Euclidean3DSpace : GeometrySpace<Vector3D>, ScaleOperations<Vector
     override val zero: Vector3D by lazy { Vector3D(0.0, 0.0, 0.0) }
 
     public fun Vector3D.norm(): Double = sqrt(x * x + y * y + z * z)
-    override fun Vector3D.unaryMinus(): Vector3D = Vector3D(-x, -y, -z)
+    override fun negate(arg: Vector3D): Vector3D = Vector3D(-arg.x, -arg.y, -arg.z)
 
     override fun Vector3D.distanceTo(other: Vector3D): Double = (this - other).norm()
 

kmath-geometry/src/commonMain/kotlin/space/kscience/kmath/geometry/Projections.kt

@@ -5,6 +5,11 @@
 
 package space.kscience.kmath.geometry
 
+import space.kscience.kmath.operations.div
+import space.kscience.kmath.operations.minus
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
+
 /**
  * Project vector onto a line.
  * @param vector to project

kmath-geometry/src/commonTest/kotlin/space/kscience/kmath/geometry/Euclidean2DSpaceTest.kt

@@ -5,6 +5,8 @@
 
 package space.kscience.kmath.geometry
 
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import kotlin.math.sqrt
 import kotlin.test.Test
 import kotlin.test.assertEquals

kmath-geometry/src/commonTest/kotlin/space/kscience/kmath/geometry/Euclidean3DSpaceTest.kt

@@ -5,6 +5,8 @@
 
 package space.kscience.kmath.geometry
 
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import kotlin.test.Test
 import kotlin.test.assertEquals
 

kmath-geometry/src/commonTest/kotlin/space/kscience/kmath/geometry/ProjectionAlongTest.kt

@@ -5,6 +5,7 @@
 
 package space.kscience.kmath.geometry
 
+import space.kscience.kmath.operations.minus
 import kotlin.test.Test
 import kotlin.test.assertTrue
 

kmath-geometry/src/commonTest/kotlin/space/kscience/kmath/geometry/ProjectionOntoLineTest.kt

@@ -5,6 +5,7 @@
 
 package space.kscience.kmath.geometry
 
+import space.kscience.kmath.operations.minus
 import kotlin.test.Test
 import kotlin.test.assertTrue
 

kmath-histograms/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     kotlin("multiplatform")
     id("ru.mipt.npm.gradle.common")
-    id("ru.mipt.npm.gradle.native")
+//    id("ru.mipt.npm.gradle.native")
 }
 
 kscience {
@@ -9,6 +9,12 @@ kscience {
 }
 
 kotlin.sourceSets {
+    filter { it.name.contains("test", true) }
+        .map(org.jetbrains.kotlin.gradle.plugin.KotlinSourceSet::languageSettings)
+        .forEach {
+            it.optIn("space.kscience.kmath.misc.UnstableKMathAPI")
+        }
+
     commonMain {
         dependencies {
             api(project(":kmath-core"))
@@ -26,3 +32,8 @@ kotlin.sourceSets {
 readme {
     maturity = ru.mipt.npm.gradle.Maturity.PROTOTYPE
 }
+
+// Testing multi-receiver!
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile> {
+    enabled = false
+}

kmath-histograms/src/commonMain/kotlin/space/kscience/kmath/histogram/Counter.kt

@@ -9,6 +9,7 @@ import kotlinx.atomicfu.atomic
 import kotlinx.atomicfu.getAndUpdate
 import space.kscience.kmath.operations.DoubleField
 import space.kscience.kmath.operations.Group
+import space.kscience.kmath.operations.plus
 
 /**
  * Common representation for atomic counters
@@ -72,5 +73,3 @@ public class ObjectCounter<T : Any>(private val group: Group<T>) : Counter<T> {
 
     override val value: T get() = innerValue.value
 }
-
-

kmath-histograms/src/commonMain/kotlin/space/kscience/kmath/histogram/HistogramND.kt

@@ -11,9 +11,7 @@ import space.kscience.kmath.nd.DefaultStrides
 import space.kscience.kmath.nd.FieldOpsND
 import space.kscience.kmath.nd.Shape
 import space.kscience.kmath.nd.StructureND
-import space.kscience.kmath.operations.Group
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.ScaleOperations
-import space.kscience.kmath.operations.invoke
 
 /**
  * @param T the type of the argument space

kmath-histograms/src/commonMain/kotlin/space/kscience/kmath/histogram/UniformHistogram1D.kt

@@ -7,10 +7,7 @@ package space.kscience.kmath.histogram
 
 import space.kscience.kmath.domains.DoubleDomain1D
 import space.kscience.kmath.misc.UnstableKMathAPI
-import space.kscience.kmath.operations.Group
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.Ring
-import space.kscience.kmath.operations.ScaleOperations
-import space.kscience.kmath.operations.invoke
 import space.kscience.kmath.structures.Buffer
 import kotlin.math.floor
 
@@ -69,8 +66,8 @@ public class UniformHistogram1DGroup<V : Any, A>(
         )
     }
 
-    override fun Histogram1D<Double, V>.unaryMinus(): UniformHistogram1D<V> = valueAlgebra {
+    override fun negate(arg: Histogram1D<Double, V>): UniformHistogram1D<V> = valueAlgebra {
-        UniformHistogram1D(this@UniformHistogram1DGroup, produceFrom(this@unaryMinus).values.mapValues { -it.value })
+        UniformHistogram1D(this@UniformHistogram1DGroup, produceFrom(arg).values.mapValues { -it.value })
     }
 
     override fun scale(

kmath-histograms/src/commonMain/kotlin/space/kscience/kmath/histogram/UniformHistogramGroupND.kt

@@ -14,6 +14,7 @@ import space.kscience.kmath.nd.*
 import space.kscience.kmath.operations.DoubleField
 import space.kscience.kmath.operations.Field
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.unaryMinus
 import space.kscience.kmath.structures.*
 import kotlin.math.floor
 
@@ -98,8 +99,8 @@ public class UniformHistogramGroupND<V : Any, A : Field<V>>(
         return HistogramND(this, values)
     }
 
-    override fun HistogramND<Double, HyperSquareDomain, V>.unaryMinus(): HistogramND<Double, HyperSquareDomain, V> =
+    override fun negate(arg: HistogramND<Double, HyperSquareDomain, V>): HistogramND<Double, HyperSquareDomain, V> =
-        this * (-1)
+        HistogramND(this, valueAlgebraND { -arg.values })
 }
 
 /**

kmath-histograms/src/commonTest/kotlin/space/kscience/kmath/histogram/MultivariateHistogramTest.kt

@@ -10,6 +10,7 @@ package space.kscience.kmath.histogram
 import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.nd.DefaultStrides
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.minus
 import space.kscience.kmath.real.DoubleVector
 import kotlin.random.Random
 import kotlin.test.*

kmath-histograms/src/commonTest/kotlin/space/kscience/kmath/histogram/UniformHistogram1DTest.kt

@@ -10,6 +10,7 @@ import kotlinx.coroutines.test.runTest
 import space.kscience.kmath.distributions.NormalDistribution
 import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.plus
 import space.kscience.kmath.stat.RandomGenerator
 import space.kscience.kmath.stat.nextBuffer
 import kotlin.native.concurrent.ThreadLocal
@@ -36,7 +37,7 @@ internal class UniformHistogram1DTest {
     @Test
     fun rebinDown() = runTest {
         val h1 = Histogram.uniform1D(DoubleField, 0.01).produce(generator.nextDoubleBuffer(10000))
-        val h2 = Histogram.uniform1D(DoubleField,0.03).produceFrom(h1)
+        val h2 = Histogram.uniform1D(DoubleField, 0.03).produceFrom(h1)
 
         assertEquals(10000, h2.bins.sumOf { it.binValue }.toInt())
     }
@@ -44,13 +45,13 @@ internal class UniformHistogram1DTest {
     @Test
     fun rebinUp() = runTest {
         val h1 = Histogram.uniform1D(DoubleField, 0.03).produce(generator.nextDoubleBuffer(10000))
-        val h2 = Histogram.uniform1D(DoubleField,0.01).produceFrom(h1)
+        val h2 = Histogram.uniform1D(DoubleField, 0.01).produceFrom(h1)
 
         assertEquals(10000, h2.bins.sumOf { it.binValue }.toInt())
     }
 
     @ThreadLocal
-    companion object{
+    companion object {
         private val generator = RandomGenerator.default(123)
     }
 }

kmath-histograms/src/jvmMain/kotlin/space/kscience/kmath/histogram/TreeHistogramGroup.kt

@@ -11,9 +11,7 @@ import space.kscience.kmath.domains.DoubleDomain1D
 import space.kscience.kmath.domains.center
 import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.misc.sorted
-import space.kscience.kmath.operations.Group
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.Ring
-import space.kscience.kmath.operations.ScaleOperations
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.first
 import space.kscience.kmath.structures.indices
@@ -123,7 +121,18 @@ public class TreeHistogramGroup<V : Any, A>(
         return TreeHistogram(bins)
     }
 
-    override fun TreeHistogram<V>.unaryMinus(): TreeHistogram<V> = this * (-1)
+    override fun negate(arg: TreeHistogram<V>): TreeHistogram<V> {
+        val bins = TreeMap<Double, Bin1D<Double, V>>().apply {
+            arg.bins.forEach { bin ->
+                put(
+                    bin.domain.center,
+                    Bin1D(bin.domain, valueAlgebra { -bin.binValue })
+                )
+            }
+        }
+
+        return TreeHistogram(bins)
+    }
 
     override val zero: TreeHistogram<V> = produce { }
 }

kmath-jafama/src/main/kotlin/space/kscience/kmath/jafama/KMathJafama.kt

@@ -29,6 +29,8 @@ public object JafamaDoubleField : ExtendedField<Double>, Norm<Double, Double>, S
         }
 
     override inline fun add(left: Double, right: Double): Double = left + right
+    override inline fun negate(arg: Double): Double = -arg
+    override inline fun subtract(left: Double, right: Double): Double = left - right
 
     override inline fun multiply(left: Double, right: Double): Double = left * right
     override inline fun divide(left: Double, right: Double): Double = left / right
@@ -55,12 +57,6 @@ public object JafamaDoubleField : ExtendedField<Double>, Norm<Double, Double>, S
     override inline fun ln(arg: Double): Double = FastMath.log(arg)
 
     override inline fun norm(arg: Double): Double = FastMath.abs(arg)
-
-    override inline fun Double.unaryMinus(): Double = -this
-    override inline fun Double.plus(arg: Double): Double = this + arg
-    override inline fun Double.minus(arg: Double): Double = this - arg
-    override inline fun Double.times(arg: Double): Double = this * arg
-    override inline fun Double.div(arg: Double): Double = this / arg
 }
 
 /**
@@ -80,6 +76,8 @@ public object StrictJafamaDoubleField : ExtendedField<Double>, Norm<Double, Doub
         }
 
     override inline fun add(left: Double, right: Double): Double = left + right
+    override inline fun negate(arg: Double): Double = -arg
+    override inline fun subtract(left: Double, right: Double): Double = left - right
 
     override inline fun multiply(left: Double, right: Double): Double = left * right
     override inline fun divide(left: Double, right: Double): Double = left / right
@@ -106,10 +104,4 @@ public object StrictJafamaDoubleField : ExtendedField<Double>, Norm<Double, Doub
     override inline fun ln(arg: Double): Double = StrictFastMath.log(arg)
 
     override inline fun norm(arg: Double): Double = StrictFastMath.abs(arg)
-
-    override inline fun Double.unaryMinus(): Double = -this
-    override inline fun Double.plus(arg: Double): Double = this + arg
-    override inline fun Double.minus(arg: Double): Double = this - arg
-    override inline fun Double.times(arg: Double): Double = this * arg
-    override inline fun Double.div(arg: Double): Double = this / arg
 }

kmath-jupyter/src/main/kotlin/space/kscience/kmath/jupyter/KMathJupyter.kt

@@ -23,6 +23,8 @@ import space.kscience.kmath.misc.PerformancePitfall
 import space.kscience.kmath.nd.Structure2D
 import space.kscience.kmath.operations.asSequence
 import space.kscience.kmath.operations.invoke
+import space.kscience.kmath.operations.plus
+import space.kscience.kmath.operations.times
 import space.kscience.kmath.structures.Buffer
 
 /**

kmath-kotlingrad/src/main/kotlin/space/kscience/kmath/kotlingrad/scalarsAdapters.kt

@@ -8,7 +8,6 @@ package space.kscience.kmath.kotlingrad
 import ai.hypergraph.kotlingrad.api.*
 import space.kscience.kmath.expressions.MST
 import space.kscience.kmath.expressions.MstExtendedField
-import space.kscience.kmath.expressions.MstExtendedField.unaryMinus
 import space.kscience.kmath.expressions.MstNumericAlgebra
 import space.kscience.kmath.expressions.Symbol
 import space.kscience.kmath.operations.*

kmath-memory/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     kotlin("multiplatform")
     id("ru.mipt.npm.gradle.common")
-    id("ru.mipt.npm.gradle.native")
+//    id("ru.mipt.npm.gradle.native")
 }
 
 readme {

kmath-memory/src/jvmMain/kotlin/space/kscience/kmath/memory/ByteBufferMemory.kt

@@ -20,8 +20,7 @@ internal class ByteBufferMemory(
     val startOffset: Int = 0,
     override val size: Int = buffer.limit(),
 ) : Memory {
-    @Suppress("NOTHING_TO_INLINE")
+    private fun position(o: Int): Int = startOffset + o
-    private inline fun position(o: Int): Int = startOffset + o
 
     override fun view(offset: Int, length: Int): Memory {
         require(offset >= 0) { "offset shouldn't be negative: $offset" }

kmath-multik/src/main/kotlin/space/kscience/kmath/multik/MultikDoubleAlgebra.kt

@@ -7,18 +7,18 @@ package space.kscience.kmath.multik
 
 import org.jetbrains.kotlinx.multik.ndarray.data.DataType
 import space.kscience.kmath.nd.StructureND
-import space.kscience.kmath.operations.DoubleField
+import space.kscience.kmath.operations.*
-import space.kscience.kmath.operations.ExponentialOperations
-import space.kscience.kmath.operations.TrigonometricOperations
 
 public object MultikDoubleAlgebra : MultikDivisionTensorAlgebra<Double, DoubleField>(),
     TrigonometricOperations<StructureND<Double>>, ExponentialOperations<StructureND<Double>> {
     override val elementAlgebra: DoubleField get() = DoubleField
     override val type: DataType get() = DataType.DoubleDataType
 
-    override fun sin(arg: StructureND<Double>): MultikTensor<Double> = multikMath.mathEx.sin(arg.asMultik().array).wrap()
+    override fun sin(arg: StructureND<Double>): MultikTensor<Double> =
+        multikMath.mathEx.sin(arg.asMultik().array).wrap()
 
-    override fun cos(arg: StructureND<Double>): MultikTensor<Double> = multikMath.mathEx.cos(arg.asMultik().array).wrap()
+    override fun cos(arg: StructureND<Double>): MultikTensor<Double> =
+        multikMath.mathEx.cos(arg.asMultik().array).wrap()
 
     override fun tan(arg: StructureND<Double>): MultikTensor<Double> = sin(arg) / cos(arg)
 
@@ -28,7 +28,8 @@ public object MultikDoubleAlgebra : MultikDivisionTensorAlgebra<Double, DoubleFi
 
     override fun atan(arg: StructureND<Double>): MultikTensor<Double> = arg.map { atan(it) }
 
-    override fun exp(arg: StructureND<Double>): MultikTensor<Double> = multikMath.mathEx.exp(arg.asMultik().array).wrap()
+    override fun exp(arg: StructureND<Double>): MultikTensor<Double> =
+        multikMath.mathEx.exp(arg.asMultik().array).wrap()
 
     override fun ln(arg: StructureND<Double>): MultikTensor<Double> = multikMath.mathEx.log(arg.asMultik().array).wrap()
 
@@ -39,7 +40,7 @@ public object MultikDoubleAlgebra : MultikDivisionTensorAlgebra<Double, DoubleFi
     override fun tanh(arg: StructureND<Double>): MultikTensor<Double> {
         val expPlus = exp(arg)
         val expMinus = exp(-arg)
-        return (expPlus - expMinus) / (expPlus + expMinus)
+        return divide((expPlus - expMinus), (expPlus + expMinus))
     }
 
     override fun asinh(arg: StructureND<Double>): MultikTensor<Double> = arg.map { asinh(it) }
@@ -51,4 +52,3 @@ public object MultikDoubleAlgebra : MultikDivisionTensorAlgebra<Double, DoubleFi
 
 public val Double.Companion.multikAlgebra: MultikTensorAlgebra<Double, DoubleField> get() = MultikDoubleAlgebra
 public val DoubleField.multikAlgebra: MultikTensorAlgebra<Double, DoubleField> get() = MultikDoubleAlgebra
-

kmath-multik/src/main/kotlin/space/kscience/kmath/multik/MultikTensorAlgebra.kt

@@ -50,7 +50,7 @@ private fun <T, D : Dimension> MultiArray<T, D>.asD2Array(): D2Array<T> {
     else throw ClassCastException("Cannot cast MultiArray to NDArray.")
 }
 
-public abstract class MultikTensorAlgebra<T, A : Ring<T>> : TensorAlgebra<T, A>
+public abstract class MultikTensorAlgebra<T, out A : Ring<T>> : TensorAlgebra<T, A>
         where T : Number, T : Comparable<T> {
 
     public abstract val type: DataType
@@ -138,14 +138,8 @@ public abstract class MultikTensorAlgebra<T, A : Ring<T>> : TensorAlgebra<T, A>
         get(intArrayOf(0))
     } else null
 
-    override fun T.plus(arg: StructureND<T>): MultikTensor<T> =
+    override fun add(left: StructureND<T>, right: StructureND<T>): MultikTensor<T> =
-        arg.plus(this)
+        left.asMultik().array.plus(right.asMultik().array).wrap()
-
-    override fun StructureND<T>.plus(arg: T): MultikTensor<T> =
-        asMultik().array.deepCopy().apply { plusAssign(arg) }.wrap()
-
-    override fun StructureND<T>.plus(arg: StructureND<T>): MultikTensor<T> =
-        asMultik().array.plus(arg.asMultik().array).wrap()
 
     override fun Tensor<T>.plusAssign(value: T) {
         if (this is MultikTensor) {
@@ -163,13 +157,8 @@ public abstract class MultikTensorAlgebra<T, A : Ring<T>> : TensorAlgebra<T, A>
         }
     }
 
-    override fun T.minus(arg: StructureND<T>): MultikTensor<T> = (-(arg.asMultik().array - this)).wrap()
+    override fun subtract(left: StructureND<T>, right: StructureND<T>): MultikTensor<T> =
-
+        left.asMultik().array.minus(right.asMultik().array).wrap()
-    override fun StructureND<T>.minus(arg: T): MultikTensor<T> =
-        asMultik().array.deepCopy().apply { minusAssign(arg) }.wrap()
-
-    override fun StructureND<T>.minus(arg: StructureND<T>): MultikTensor<T> =
-        asMultik().array.minus(arg.asMultik().array).wrap()
 
     override fun Tensor<T>.minusAssign(value: T) {
         if (this is MultikTensor) {
@@ -187,14 +176,8 @@ public abstract class MultikTensorAlgebra<T, A : Ring<T>> : TensorAlgebra<T, A>
         }
     }
 
-    override fun T.times(arg: StructureND<T>): MultikTensor<T> =
+    override fun multiply(left: StructureND<T>, right: StructureND<T>): MultikTensor<T> =
-        arg.asMultik().array.deepCopy().apply { timesAssign(this@times) }.wrap()
+        left.asMultik().array.times(right.asMultik().array).wrap()
-
-    override fun StructureND<T>.times(arg: T): Tensor<T> =
-        asMultik().array.deepCopy().apply { timesAssign(arg) }.wrap()
-
-    override fun StructureND<T>.times(arg: StructureND<T>): MultikTensor<T> =
-        asMultik().array.times(arg.asMultik().array).wrap()
 
     override fun Tensor<T>.timesAssign(value: T) {
         if (this is MultikTensor) {
@@ -212,12 +195,11 @@ public abstract class MultikTensorAlgebra<T, A : Ring<T>> : TensorAlgebra<T, A>
         }
     }
 
-    override fun StructureND<T>.unaryMinus(): MultikTensor<T> =
+    override fun negate(arg: StructureND<T>): MultikTensor<T> = (-arg.asMultik().array).wrap()
-        asMultik().array.unaryMinus().wrap()
 
     override fun Tensor<T>.get(i: Int): MultikTensor<T> = asMultik().array.mutableView(i).wrap()
 
-    override fun Tensor<T>.transpose(i: Int, j: Int): MultikTensor<T> = asMultik().array.transpose(i, j).wrap()
+    override fun StructureND<T>.transpose(i: Int, j: Int): MultikTensor<T> = asMultik().array.transpose(i, j).wrap()
 
     override fun Tensor<T>.view(shape: IntArray): MultikTensor<T> {
         require(shape.all { it > 0 })
@@ -282,16 +264,36 @@ public abstract class MultikTensorAlgebra<T, A : Ring<T>> : TensorAlgebra<T, A>
     }
 }
 
-public abstract class MultikDivisionTensorAlgebra<T, A : Field<T>>
+context(MultikTensorAlgebra<T, A>)
+public operator fun <T, A : Ring<T>> T.plus(arg: StructureND<T>): MultikTensor<T> where T : Comparable<T>, T : Number =
+    arg.plus(this)
+
+context(MultikTensorAlgebra<T, A>)
+public operator fun <T, A : Ring<T>> StructureND<T>.plus(arg: T): MultikTensor<T> where T : Comparable<T>, T : Number =
+    asMultik().array.deepCopy().apply { plusAssign(arg) }.wrap()
+
+context(MultikTensorAlgebra<T, A>)
+public operator fun <T, A : Ring<T>> T.minus(arg: StructureND<T>): MultikTensor<T> where T : Comparable<T>, T : Number =
+    (-(arg.asMultik().array - this)).wrap()
+
+context(MultikTensorAlgebra<T, A>)
+public operator fun <T, A : Ring<T>> StructureND<T>.minus(arg: T): MultikTensor<T> where T : Comparable<T>, T : Number =
+    asMultik().array.deepCopy().apply { minusAssign(arg) }.wrap()
+
+context(MultikTensorAlgebra<T, A>)
+public operator fun <T, A : Ring<T>> T.times(arg: StructureND<T>): MultikTensor<T> where T : Comparable<T>, T : Number =
+    arg.asMultik().array.deepCopy().apply { timesAssign(this@times) }.wrap()
+
+context(MultikTensorAlgebra<T, A>)
+public operator fun <T, A : Ring<T>> StructureND<T>.times(arg: T): Tensor<T> where T : Comparable<T>, T : Number =
+    asMultik().array.deepCopy().apply { timesAssign(arg) }.wrap()
+
+
+public abstract class MultikDivisionTensorAlgebra<T, out A : Field<T>>
     : MultikTensorAlgebra<T, A>(), TensorPartialDivisionAlgebra<T, A> where T : Number, T : Comparable<T> {
 
-    override fun T.div(arg: StructureND<T>): MultikTensor<T> = arg.map { elementAlgebra.divide(this@div, it) }
+    override fun divide(left: StructureND<T>, right: StructureND<T>): MultikTensor<T> =
-
+        left.asMultik().array.div(right.asMultik().array).wrap()
-    override fun StructureND<T>.div(arg: T): MultikTensor<T> =
-        asMultik().array.deepCopy().apply { divAssign(arg) }.wrap()
-
-    override fun StructureND<T>.div(arg: StructureND<T>): MultikTensor<T> =
-        asMultik().array.div(arg.asMultik().array).wrap()
 
     override fun Tensor<T>.divAssign(value: T) {
         if (this is MultikTensor) {
@@ -310,6 +312,18 @@ public abstract class MultikDivisionTensorAlgebra<T, A : Field<T>>
     }
 }
 
+context(MultikDivisionTensorAlgebra<T, A>)
+public operator fun <T, A : Field<T>> StructureND<T>.div(arg: StructureND<T>): MultikTensor<T> where T : Number, T : Comparable<T> =
+    divide(this, arg)
+
+context(MultikDivisionTensorAlgebra<T, A>)
+public operator fun <T, A : Field<T>> T.div(arg: StructureND<T>): MultikTensor<T> where T : Number, T : Comparable<T> =
+    arg.map { elementAlgebra.divide(this@div, it) }
+
+context(MultikDivisionTensorAlgebra<T, A>)
+public operator fun <T, A : Field<T>> StructureND<T>.div(arg: T): MultikTensor<T> where T : Number, T : Comparable<T> =
+    asMultik().array.deepCopy().apply { divAssign(arg) }.wrap()
+
 public object MultikFloatAlgebra : MultikDivisionTensorAlgebra<Float, FloatField>() {
     override val elementAlgebra: FloatField get() = FloatField
     override val type: DataType get() = DataType.FloatDataType

kmath-nd4j/src/main/kotlin/space/kscience/kmath/nd4j/Nd4jArrayAlgebra.kt

@@ -45,6 +45,7 @@ public sealed interface Nd4jArrayAlgebra<T, out C : Algebra<T>> : AlgebraND<T, C
         return newStruct
     }
 
+    @OptIn(PerformancePitfall::class)
     override fun StructureND<T>.mapIndexed(
         transform: C.(index: IntArray, T) -> T,
     ): Nd4jArrayStructure<T> {
@@ -53,6 +54,7 @@ public sealed interface Nd4jArrayAlgebra<T, out C : Algebra<T>> : AlgebraND<T, C
         return new
     }
 
+    @OptIn(PerformancePitfall::class)
     override fun zip(
         left: StructureND<T>,
         right: StructureND<T>,
@@ -72,15 +74,14 @@ public sealed interface Nd4jArrayAlgebra<T, out C : Algebra<T>> : AlgebraND<T, C
  * @param S the type of space of structure elements.
  */
 public sealed interface Nd4jArrayGroupOps<T, out S : Ring<T>> : GroupOpsND<T, S>, Nd4jArrayAlgebra<T, S> {
-
     override fun add(left: StructureND<T>, right: StructureND<T>): Nd4jArrayStructure<T> =
         left.ndArray.add(right.ndArray).wrap()
 
-    override operator fun StructureND<T>.minus(arg: StructureND<T>): Nd4jArrayStructure<T> =
+    override fun subtract(left: StructureND<T>, right: StructureND<T>): Nd4jArrayStructure<T> =
-        ndArray.sub(arg.ndArray).wrap()
+        left.ndArray.sub(right.ndArray).wrap()
 
-    override operator fun StructureND<T>.unaryMinus(): Nd4jArrayStructure<T> =
+    override fun negate(arg: StructureND<T>): Nd4jArrayStructure<T> =
-        ndArray.neg().wrap()
+        arg.ndArray.neg().wrap()
 
     public fun multiply(a: StructureND<T>, k: Number): Nd4jArrayStructure<T> =
         a.ndArray.mul(k).wrap()
@@ -92,7 +93,6 @@ public sealed interface Nd4jArrayGroupOps<T, out S : Ring<T>> : GroupOpsND<T, S>
  * @param T the type of the element contained in ND structure.
  * @param R the type of ring of structure elements.
  */
-@OptIn(UnstableKMathAPI::class)
 public sealed interface Nd4jArrayRingOps<T, out R : Ring<T>> : RingOpsND<T, R>, Nd4jArrayGroupOps<T, R> {
 
     override fun multiply(left: StructureND<T>, right: StructureND<T>): Nd4jArrayStructure<T> =
@@ -201,23 +201,29 @@ public open class DoubleNd4jArrayFieldOps : Nd4jArrayExtendedFieldOps<Double, Do
 
     override fun scale(a: StructureND<Double>, value: Double): Nd4jArrayStructure<Double> = a.ndArray.mul(value).wrap()
 
-    override operator fun StructureND<Double>.div(arg: Double): Nd4jArrayStructure<Double> = ndArray.div(arg).wrap()
-
-    override operator fun StructureND<Double>.plus(arg: Double): Nd4jArrayStructure<Double> = ndArray.add(arg).wrap()
-
-    override operator fun StructureND<Double>.minus(arg: Double): Nd4jArrayStructure<Double> = ndArray.sub(arg).wrap()
-
-    override operator fun StructureND<Double>.times(arg: Double): Nd4jArrayStructure<Double> = ndArray.mul(arg).wrap()
-
-    override operator fun Double.div(arg: StructureND<Double>): Nd4jArrayStructure<Double> =
-        arg.ndArray.rdiv(this).wrap()
-
-    override operator fun Double.minus(arg: StructureND<Double>): Nd4jArrayStructure<Double> =
-        arg.ndArray.rsub(this).wrap()
-
     public companion object : DoubleNd4jArrayFieldOps()
 }
 
+context(DoubleNd4jArrayFieldOps)
+public operator fun StructureND<Double>.div(arg: Double): Nd4jArrayStructure<Double> = ndArray.div(arg).wrap()
+
+context(DoubleNd4jArrayFieldOps)
+public operator fun StructureND<Double>.plus(arg: Double): Nd4jArrayStructure<Double> = ndArray.add(arg).wrap()
+
+context(DoubleNd4jArrayFieldOps)
+public operator fun StructureND<Double>.minus(arg: Double): Nd4jArrayStructure<Double> = ndArray.sub(arg).wrap()
+
+context(DoubleNd4jArrayFieldOps)
+public operator fun StructureND<Double>.times(arg: Double): Nd4jArrayStructure<Double> = ndArray.mul(arg).wrap()
+
+context(DoubleNd4jArrayFieldOps)
+public operator fun Double.div(arg: StructureND<Double>): Nd4jArrayStructure<Double> =
+    arg.ndArray.rdiv(this).wrap()
+
+context(DoubleNd4jArrayFieldOps)
+public operator fun Double.minus(arg: StructureND<Double>): Nd4jArrayStructure<Double> =
+    arg.ndArray.rsub(this).wrap()
+
 public val DoubleField.nd4j: DoubleNd4jArrayFieldOps get() = DoubleNd4jArrayFieldOps
 
 public class DoubleNd4jArrayField(override val shape: Shape) : DoubleNd4jArrayFieldOps(), FieldND<Double, DoubleField>
@@ -246,27 +252,33 @@ public open class FloatNd4jArrayFieldOps : Nd4jArrayExtendedFieldOps<Float, Floa
     override fun scale(a: StructureND<Float>, value: Double): StructureND<Float> =
         a.ndArray.mul(value).wrap()
 
-    override operator fun StructureND<Float>.div(arg: Float): Nd4jArrayStructure<Float> =
-        ndArray.div(arg).wrap()
-
-    override operator fun StructureND<Float>.plus(arg: Float): Nd4jArrayStructure<Float> =
-        ndArray.add(arg).wrap()
-
-    override operator fun StructureND<Float>.minus(arg: Float): Nd4jArrayStructure<Float> =
-        ndArray.sub(arg).wrap()
-
-    override operator fun StructureND<Float>.times(arg: Float): Nd4jArrayStructure<Float> =
-        ndArray.mul(arg).wrap()
-
-    override operator fun Float.div(arg: StructureND<Float>): Nd4jArrayStructure<Float> =
-        arg.ndArray.rdiv(this).wrap()
-
-    override operator fun Float.minus(arg: StructureND<Float>): Nd4jArrayStructure<Float> =
-        arg.ndArray.rsub(this).wrap()
-
     public companion object : FloatNd4jArrayFieldOps()
 }
 
+context(FloatNd4jArrayFieldOps)
+public operator fun StructureND<Float>.div(arg: Float): Nd4jArrayStructure<Float> =
+    ndArray.div(arg).wrap()
+
+context(FloatNd4jArrayFieldOps)
+public operator fun StructureND<Float>.plus(arg: Float): Nd4jArrayStructure<Float> =
+    ndArray.add(arg).wrap()
+
+context(FloatNd4jArrayFieldOps)
+public operator fun StructureND<Float>.minus(arg: Float): Nd4jArrayStructure<Float> =
+    ndArray.sub(arg).wrap()
+
+context(FloatNd4jArrayFieldOps)
+public operator fun StructureND<Float>.times(arg: Float): Nd4jArrayStructure<Float> =
+    ndArray.mul(arg).wrap()
+
+context(FloatNd4jArrayFieldOps)
+public operator fun Float.div(arg: StructureND<Float>): Nd4jArrayStructure<Float> =
+    arg.ndArray.rdiv(this).wrap()
+
+context(FloatNd4jArrayFieldOps)
+public operator fun Float.minus(arg: StructureND<Float>): Nd4jArrayStructure<Float> =
+    arg.ndArray.rsub(this).wrap()
+
 public class FloatNd4jArrayField(override val shape: Shape) : FloatNd4jArrayFieldOps(), RingND<Float, FloatField>
 
 public val FloatField.nd4j: FloatNd4jArrayFieldOps get() = FloatNd4jArrayFieldOps
@@ -291,21 +303,25 @@ public open class IntNd4jArrayRingOps : Nd4jArrayRingOps<Int, IntRing> {
             }
         }
 
-    override operator fun StructureND<Int>.plus(arg: Int): Nd4jArrayStructure<Int> =
-        ndArray.add(arg).wrap()
-
-    override operator fun StructureND<Int>.minus(arg: Int): Nd4jArrayStructure<Int> =
-        ndArray.sub(arg).wrap()
-
-    override operator fun StructureND<Int>.times(arg: Int): Nd4jArrayStructure<Int> =
-        ndArray.mul(arg).wrap()
-
-    override operator fun Int.minus(arg: StructureND<Int>): Nd4jArrayStructure<Int> =
-        arg.ndArray.rsub(this).wrap()
-
     public companion object : IntNd4jArrayRingOps()
 }
 
+context(IntNd4jArrayRingOps)
+public operator fun StructureND<Int>.plus(arg: Int): Nd4jArrayStructure<Int> =
+    ndArray.add(arg).wrap()
+
+context(IntNd4jArrayRingOps)
+public operator fun StructureND<Int>.minus(arg: Int): Nd4jArrayStructure<Int> =
+    ndArray.sub(arg).wrap()
+
+context(IntNd4jArrayRingOps)
+public operator fun StructureND<Int>.times(arg: Int): Nd4jArrayStructure<Int> =
+    ndArray.mul(arg).wrap()
+
+context(IntNd4jArrayRingOps)
+public operator fun Int.minus(arg: StructureND<Int>): Nd4jArrayStructure<Int> =
+    arg.ndArray.rsub(this).wrap()
+
 public val IntRing.nd4j: IntNd4jArrayRingOps get() = IntNd4jArrayRingOps
 
 public class IntNd4jArrayRing(override val shape: Shape) : IntNd4jArrayRingOps(), RingND<Int, IntRing>

kmath-nd4j/src/main/kotlin/space/kscience/kmath/nd4j/Nd4jTensorAlgebra.kt

@@ -16,6 +16,7 @@ import space.kscience.kmath.misc.PerformancePitfall
 import space.kscience.kmath.nd.DefaultStrides
 import space.kscience.kmath.nd.Shape
 import space.kscience.kmath.nd.StructureND
+import space.kscience.kmath.operations.Algebra
 import space.kscience.kmath.operations.DoubleField
 import space.kscience.kmath.operations.Field
 import space.kscience.kmath.tensors.api.AnalyticTensorAlgebra
@@ -26,7 +27,7 @@ import space.kscience.kmath.tensors.core.DoubleTensorAlgebra
 /**
  * ND4J based [TensorAlgebra] implementation.
  */
-public sealed interface Nd4jTensorAlgebra<T : Number, A : Field<T>> : AnalyticTensorAlgebra<T, A> {
+public sealed interface Nd4jTensorAlgebra<T : Number, out A : Field<T>> : AnalyticTensorAlgebra<T, A> {
 
     /**
      * Wraps [INDArray] to [Nd4jArrayStructure].
@@ -51,10 +52,8 @@ public sealed interface Nd4jTensorAlgebra<T : Number, A : Field<T>> : AnalyticTe
         return structureND(left.shape) { index -> elementAlgebra.transform(left[index], right[index]) }
     }
 
-    override fun T.plus(arg: StructureND<T>): Nd4jArrayStructure<T> = arg.ndArray.add(this).wrap()
+    override fun add(left: StructureND<T>, right: StructureND<T>): Nd4jArrayStructure<T> =
-    override fun StructureND<T>.plus(arg: T): Nd4jArrayStructure<T> = ndArray.add(arg).wrap()
+        left.ndArray.add(right.ndArray).wrap()
-
-    override fun StructureND<T>.plus(arg: StructureND<T>): Nd4jArrayStructure<T> = ndArray.add(arg.ndArray).wrap()
 
     override fun Tensor<T>.plusAssign(value: T) {
         ndArray.addi(value)
@@ -64,9 +63,8 @@ public sealed interface Nd4jTensorAlgebra<T : Number, A : Field<T>> : AnalyticTe
         ndArray.addi(arg.ndArray)
     }
 
-    override fun T.minus(arg: StructureND<T>): Nd4jArrayStructure<T> = arg.ndArray.rsub(this).wrap()
+    override fun subtract(left: StructureND<T>, right: StructureND<T>): Nd4jArrayStructure<T> =
-    override fun StructureND<T>.minus(arg: T): Nd4jArrayStructure<T> = ndArray.sub(arg).wrap()
+        left.ndArray.sub(right.ndArray).wrap()
-    override fun StructureND<T>.minus(arg: StructureND<T>): Nd4jArrayStructure<T> = ndArray.sub(arg.ndArray).wrap()
 
     override fun Tensor<T>.minusAssign(value: T) {
         ndArray.rsubi(value)
@@ -76,12 +74,7 @@ public sealed interface Nd4jTensorAlgebra<T : Number, A : Field<T>> : AnalyticTe
         ndArray.subi(arg.ndArray)
     }
 
-    override fun T.times(arg: StructureND<T>): Nd4jArrayStructure<T> = arg.ndArray.mul(this).wrap()
+    override fun multiply(left: StructureND<T>, right: StructureND<T>): Nd4jArrayStructure<T> = left.ndArray.mul(right.ndArray).wrap()
-
-    override fun StructureND<T>.times(arg: T): Nd4jArrayStructure<T> =
-        ndArray.mul(arg).wrap()
-
-    override fun StructureND<T>.times(arg: StructureND<T>): Nd4jArrayStructure<T> = ndArray.mul(arg.ndArray).wrap()
 
     override fun Tensor<T>.timesAssign(value: T) {
         ndArray.muli(value)
@@ -91,9 +84,9 @@ public sealed interface Nd4jTensorAlgebra<T : Number, A : Field<T>> : AnalyticTe
         ndArray.mmuli(arg.ndArray)
     }
 
-    override fun StructureND<T>.unaryMinus(): Nd4jArrayStructure<T> = ndArray.neg().wrap()
+    override fun negate(arg: StructureND<T>): Nd4jArrayStructure<T> = arg.ndArray.neg().wrap()
     override fun Tensor<T>.get(i: Int): Nd4jArrayStructure<T> = ndArray.slice(i.toLong()).wrap()
-    override fun Tensor<T>.transpose(i: Int, j: Int): Nd4jArrayStructure<T> = ndArray.swapAxes(i, j).wrap()
+    override fun StructureND<T>.transpose(i: Int, j: Int): Nd4jArrayStructure<T> = ndArray.swapAxes(i, j).wrap()
     override fun StructureND<T>.dot(other: StructureND<T>): Nd4jArrayStructure<T> = ndArray.mmul(other.ndArray).wrap()
 
     override fun StructureND<T>.min(dim: Int, keepDim: Boolean): Nd4jArrayStructure<T> =
@@ -140,9 +133,7 @@ public sealed interface Nd4jTensorAlgebra<T : Number, A : Field<T>> : AnalyticTe
     override fun StructureND<T>.std(dim: Int, keepDim: Boolean): Nd4jArrayStructure<T> =
         ndArray.std(true, keepDim, dim).wrap()
 
-    override fun T.div(arg: StructureND<T>): Nd4jArrayStructure<T> = arg.ndArray.rdiv(this).wrap()
+    override fun divide(left: StructureND<T>, right: StructureND<T>): Nd4jArrayStructure<T> = left.ndArray.div(right.ndArray).wrap()
-    override fun StructureND<T>.div(arg: T): Nd4jArrayStructure<T> = ndArray.div(arg).wrap()
-    override fun StructureND<T>.div(arg: StructureND<T>): Nd4jArrayStructure<T> = ndArray.div(arg.ndArray).wrap()
 
     override fun Tensor<T>.divAssign(value: T) {
         ndArray.divi(value)
@@ -160,6 +151,36 @@ public sealed interface Nd4jTensorAlgebra<T : Number, A : Field<T>> : AnalyticTe
     }
 }
 
+context(Nd4jTensorAlgebra<T, C>)
+public fun <T : Number, C : Field<T>> T.plus(arg: StructureND<T>): Nd4jArrayStructure<T> = arg.ndArray.add(this).wrap()
+
+context(Nd4jTensorAlgebra<T, C>)
+public fun <T : Number, C : Field<T>> StructureND<T>.plus(arg: T): Nd4jArrayStructure<T> = ndArray.add(arg).wrap()
+
+context(Nd4jTensorAlgebra<T, C>)
+public fun <T : Number, C : Field<T>> T.times(arg: StructureND<T>): Nd4jArrayStructure<T> =
+    arg.ndArray.mul(this).wrap()
+
+context(Nd4jTensorAlgebra<T, C>)
+public fun <T : Number, C : Field<T>> StructureND<T>.times(arg: T): Nd4jArrayStructure<T> =
+    ndArray.mul(arg).wrap()
+
+context(Nd4jTensorAlgebra<T, C>)
+public operator fun <T : Number, C : Field<T>> T.minus(arg: StructureND<T>): Nd4jArrayStructure<T> =
+    arg.ndArray.rsub(this).wrap()
+
+context(Nd4jTensorAlgebra<T, C>)
+public operator fun <T:Number,C : Field<T>> StructureND<T>.minus(arg: T): Nd4jArrayStructure<T> =
+    ndArray.sub(arg).wrap()
+
+context(Nd4jTensorAlgebra<T, C>)
+public operator fun <T : Number, C : Field<T>> T.div(arg: StructureND<T>): Nd4jArrayStructure<T> =
+    arg.ndArray.rdiv(this).wrap()
+
+context(Nd4jTensorAlgebra<T, C>)
+public operator fun <T : Number, C : Field<T>> StructureND<T>.div(arg: T): Nd4jArrayStructure<T> =
+    ndArray.div(arg).wrap()
+
 /**
  * [Double] specialization of [Nd4jTensorAlgebra].
  */

kmath-optimization/build.gradle.kts

@@ -1,6 +1,6 @@
 plugins {
     id("ru.mipt.npm.gradle.mpp")
-    id("ru.mipt.npm.gradle.native")
+//    id("ru.mipt.npm.gradle.native")
 }
 
 kscience {
@@ -22,3 +22,8 @@ kotlin.sourceSets {
 readme {
     maturity = ru.mipt.npm.gradle.Maturity.EXPERIMENTAL
 }
+
+// Testing multi-receiver!
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.Kotlin2JsCompile> {
+    enabled = false
+}