CHANGELOG.md

@@ -76,6 +76,7 @@
 - `toGrid` method.
 - Public visibility of `BufferAccessor2D`
 - `Real` class
+- StructureND identity and equals
 
 ### Fixed
 - `symbol` method in `MstExtendedField` (https://github.com/mipt-npm/kmath/pull/140)

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

@@ -20,10 +20,10 @@ class StreamDoubleFieldND(
 
     private val strides = DefaultStrides(shape)
     override val elementContext: DoubleField get() = DoubleField
-    override val zero: NDBuffer<Double> by lazy { produce { zero } }
+    override val zero: BufferND<Double> by lazy { produce { zero } }
-    override val one: NDBuffer<Double> by lazy { produce { one } }
+    override val one: BufferND<Double> by lazy { produce { one } }
 
-    override fun number(value: Number): NDBuffer<Double> {
+    override fun number(value: Number): BufferND<Double> {
         val d = value.toDouble() // minimize conversions
         return produce { d }
     }
@@ -34,30 +34,30 @@ class StreamDoubleFieldND(
                 this@StreamDoubleFieldND.shape,
                 shape
             )
-            this is NDBuffer && this.strides == this@StreamDoubleFieldND.strides -> this.buffer as DoubleBuffer
+            this is BufferND && this.strides == this@StreamDoubleFieldND.strides -> this.buffer as DoubleBuffer
             else -> DoubleBuffer(strides.linearSize) { offset -> get(strides.index(offset)) }
         }
 
 
-    override fun produce(initializer: DoubleField.(IntArray) -> Double): NDBuffer<Double> {
+    override fun produce(initializer: DoubleField.(IntArray) -> Double): BufferND<Double> {
         val array = IntStream.range(0, strides.linearSize).parallel().mapToDouble { offset ->
             val index = strides.index(offset)
             DoubleField.initializer(index)
         }.toArray()
 
-        return NDBuffer(strides, array.asBuffer())
+        return BufferND(strides, array.asBuffer())
     }
 
     override fun StructureND<Double>.map(
         transform: DoubleField.(Double) -> Double,
-    ): NDBuffer<Double> {
+    ): BufferND<Double> {
         val array = Arrays.stream(buffer.array).parallel().map { DoubleField.transform(it) }.toArray()
-        return NDBuffer(strides, array.asBuffer())
+        return BufferND(strides, array.asBuffer())
     }
 
     override fun StructureND<Double>.mapIndexed(
         transform: DoubleField.(index: IntArray, Double) -> Double,
-    ): NDBuffer<Double> {
+    ): BufferND<Double> {
         val array = IntStream.range(0, strides.linearSize).parallel().mapToDouble { offset ->
             DoubleField.transform(
                 strides.index(offset),
@@ -65,43 +65,43 @@ class StreamDoubleFieldND(
             )
         }.toArray()
 
-        return NDBuffer(strides, array.asBuffer())
+        return BufferND(strides, array.asBuffer())
     }
 
     override fun combine(
         a: StructureND<Double>,
         b: StructureND<Double>,
         transform: DoubleField.(Double, Double) -> Double,
-    ): NDBuffer<Double> {
+    ): BufferND<Double> {
         val array = IntStream.range(0, strides.linearSize).parallel().mapToDouble { offset ->
             DoubleField.transform(a.buffer.array[offset], b.buffer.array[offset])
         }.toArray()
-        return NDBuffer(strides, array.asBuffer())
+        return BufferND(strides, array.asBuffer())
     }
 
     override fun StructureND<Double>.unaryMinus(): StructureND<Double> = map { -it }
 
     override fun scale(a: StructureND<Double>, value: Double): StructureND<Double> = a.map { it * value }
 
-    override fun power(arg: StructureND<Double>, pow: Number): NDBuffer<Double> = arg.map { power(it, pow) }
+    override fun power(arg: StructureND<Double>, pow: Number): BufferND<Double> = arg.map { power(it, pow) }
 
-    override fun exp(arg: StructureND<Double>): NDBuffer<Double> = arg.map { exp(it) }
+    override fun exp(arg: StructureND<Double>): BufferND<Double> = arg.map { exp(it) }
 
-    override fun ln(arg: StructureND<Double>): NDBuffer<Double> = arg.map { ln(it) }
+    override fun ln(arg: StructureND<Double>): BufferND<Double> = arg.map { ln(it) }
 
-    override fun sin(arg: StructureND<Double>): NDBuffer<Double> = arg.map { sin(it) }
+    override fun sin(arg: StructureND<Double>): BufferND<Double> = arg.map { sin(it) }
-    override fun cos(arg: StructureND<Double>): NDBuffer<Double> = arg.map { cos(it) }
+    override fun cos(arg: StructureND<Double>): BufferND<Double> = arg.map { cos(it) }
-    override fun tan(arg: StructureND<Double>): NDBuffer<Double> = arg.map { tan(it) }
+    override fun tan(arg: StructureND<Double>): BufferND<Double> = arg.map { tan(it) }
-    override fun asin(arg: StructureND<Double>): NDBuffer<Double> = arg.map { asin(it) }
+    override fun asin(arg: StructureND<Double>): BufferND<Double> = arg.map { asin(it) }
-    override fun acos(arg: StructureND<Double>): NDBuffer<Double> = arg.map { acos(it) }
+    override fun acos(arg: StructureND<Double>): BufferND<Double> = arg.map { acos(it) }
-    override fun atan(arg: StructureND<Double>): NDBuffer<Double> = arg.map { atan(it) }
+    override fun atan(arg: StructureND<Double>): BufferND<Double> = arg.map { atan(it) }
 
-    override fun sinh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { sinh(it) }
+    override fun sinh(arg: StructureND<Double>): BufferND<Double> = arg.map { sinh(it) }
-    override fun cosh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { cosh(it) }
+    override fun cosh(arg: StructureND<Double>): BufferND<Double> = arg.map { cosh(it) }
-    override fun tanh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { tanh(it) }
+    override fun tanh(arg: StructureND<Double>): BufferND<Double> = arg.map { tanh(it) }
-    override fun asinh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { asinh(it) }
+    override fun asinh(arg: StructureND<Double>): BufferND<Double> = arg.map { asinh(it) }
-    override fun acosh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { acosh(it) }
+    override fun acosh(arg: StructureND<Double>): BufferND<Double> = arg.map { acosh(it) }
-    override fun atanh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { atanh(it) }
+    override fun atanh(arg: StructureND<Double>): BufferND<Double> = arg.map { atanh(it) }
 }
 
 fun AlgebraND.Companion.realWithStream(vararg shape: Int): StreamDoubleFieldND = StreamDoubleFieldND(shape)

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

@@ -1,7 +1,7 @@
 package space.kscience.kmath.structures
 
+import space.kscience.kmath.nd.BufferND
 import space.kscience.kmath.nd.DefaultStrides
-import space.kscience.kmath.nd.NDBuffer
 import kotlin.system.measureTimeMillis
 
 @Suppress("ASSIGNED_BUT_NEVER_ACCESSED_VARIABLE")
@@ -10,7 +10,7 @@ fun main() {
     val array = DoubleArray(n * n) { 1.0 }
     val buffer = DoubleBuffer(array)
     val strides = DefaultStrides(intArrayOf(n, n))
-    val structure = NDBuffer(strides, buffer)
+    val structure = BufferND(strides, buffer)
 
     measureTimeMillis {
         var res = 0.0

kmath-commons/src/main/kotlin/space/kscience/kmath/commons/linear/CMMatrix.kt

@@ -3,25 +3,16 @@ package space.kscience.kmath.commons.linear
 import org.apache.commons.math3.linear.*
 import space.kscience.kmath.linear.*
 import space.kscience.kmath.misc.UnstableKMathAPI
-import space.kscience.kmath.nd.StructureND
 import space.kscience.kmath.operations.DoubleField
 import space.kscience.kmath.structures.DoubleBuffer
 import kotlin.reflect.KClass
 import kotlin.reflect.cast
 
-public class CMMatrix(public val origin: RealMatrix) : Matrix<Double> {
+public inline class CMMatrix(public val origin: RealMatrix) : Matrix<Double> {
     public override val rowNum: Int get() = origin.rowDimension
     public override val colNum: Int get() = origin.columnDimension
 
     public override operator fun get(i: Int, j: Int): Double = origin.getEntry(i, j)
-
-    override fun equals(other: Any?): Boolean {
-        if (this === other) return true
-        if (other !is StructureND<*>) return false
-        return StructureND.contentEquals(this, other)
-    }
-
-    override fun hashCode(): Int = origin.hashCode()
 }
 
 public inline class CMVector(public val origin: RealVector) : Point<Double> {

kmath-commons/src/main/kotlin/space/kscience/kmath/commons/transform/Transformations.kt

@@ -6,9 +6,11 @@ import kotlinx.coroutines.flow.map
 import org.apache.commons.math3.transform.*
 import space.kscience.kmath.complex.Complex
 import space.kscience.kmath.streaming.chunked
+import space.kscience.kmath.streaming.spread
 import space.kscience.kmath.structures.*
 
 
+
 /**
  * Streaming and buffer transformations
  */

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

@@ -2,8 +2,8 @@ package space.kscience.kmath.complex
 
 import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.nd.AlgebraND
+import space.kscience.kmath.nd.BufferND
 import space.kscience.kmath.nd.BufferedFieldND
-import space.kscience.kmath.nd.NDBuffer
 import space.kscience.kmath.nd.StructureND
 import space.kscience.kmath.operations.ExtendedField
 import space.kscience.kmath.operations.NumbersAddOperations
@@ -22,10 +22,10 @@ public class ComplexFieldND(
     NumbersAddOperations<StructureND<Complex>>,
     ExtendedField<StructureND<Complex>> {
 
-    override val zero: NDBuffer<Complex> by lazy { produce { zero } }
+    override val zero: BufferND<Complex> by lazy { produce { zero } }
-    override val one: NDBuffer<Complex> by lazy { produce { one } }
+    override val one: BufferND<Complex> by lazy { produce { one } }
 
-    override fun number(value: Number): NDBuffer<Complex> {
+    override fun number(value: Number): BufferND<Complex> {
         val d = value.toComplex() // minimize conversions
         return produce { d }
     }
@@ -76,35 +76,35 @@ public class ComplexFieldND(
 //        return BufferedNDFieldElement(this, buffer)
 //    }
 
-    override fun power(arg: StructureND<Complex>, pow: Number): NDBuffer<Complex> = arg.map { power(it, pow) }
+    override fun power(arg: StructureND<Complex>, pow: Number): BufferND<Complex> = arg.map { power(it, pow) }
 
-    override fun exp(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { exp(it) }
+    override fun exp(arg: StructureND<Complex>): BufferND<Complex> = arg.map { exp(it) }
 
-    override fun ln(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { ln(it) }
+    override fun ln(arg: StructureND<Complex>): BufferND<Complex> = arg.map { ln(it) }
 
-    override fun sin(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { sin(it) }
+    override fun sin(arg: StructureND<Complex>): BufferND<Complex> = arg.map { sin(it) }
-    override fun cos(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { cos(it) }
+    override fun cos(arg: StructureND<Complex>): BufferND<Complex> = arg.map { cos(it) }
-    override fun tan(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { tan(it) }
+    override fun tan(arg: StructureND<Complex>): BufferND<Complex> = arg.map { tan(it) }
-    override fun asin(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { asin(it) }
+    override fun asin(arg: StructureND<Complex>): BufferND<Complex> = arg.map { asin(it) }
-    override fun acos(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { acos(it) }
+    override fun acos(arg: StructureND<Complex>): BufferND<Complex> = arg.map { acos(it) }
-    override fun atan(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { atan(it) }
+    override fun atan(arg: StructureND<Complex>): BufferND<Complex> = arg.map { atan(it) }
 
-    override fun sinh(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { sinh(it) }
+    override fun sinh(arg: StructureND<Complex>): BufferND<Complex> = arg.map { sinh(it) }
-    override fun cosh(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { cosh(it) }
+    override fun cosh(arg: StructureND<Complex>): BufferND<Complex> = arg.map { cosh(it) }
-    override fun tanh(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { tanh(it) }
+    override fun tanh(arg: StructureND<Complex>): BufferND<Complex> = arg.map { tanh(it) }
-    override fun asinh(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { asinh(it) }
+    override fun asinh(arg: StructureND<Complex>): BufferND<Complex> = arg.map { asinh(it) }
-    override fun acosh(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { acosh(it) }
+    override fun acosh(arg: StructureND<Complex>): BufferND<Complex> = arg.map { acosh(it) }
-    override fun atanh(arg: StructureND<Complex>): NDBuffer<Complex> = arg.map { atanh(it) }
+    override fun atanh(arg: StructureND<Complex>): BufferND<Complex> = arg.map { atanh(it) }
 }
 
 
 /**
  * Fast element production using function inlining
  */
-public inline fun BufferedFieldND<Complex, ComplexField>.produceInline(initializer: ComplexField.(Int) -> Complex): NDBuffer<Complex> {
+public inline fun BufferedFieldND<Complex, ComplexField>.produceInline(initializer: ComplexField.(Int) -> Complex): BufferND<Complex> {
     contract { callsInPlace(initializer, InvocationKind.EXACTLY_ONCE) }
     val buffer = Buffer.complex(strides.linearSize) { offset -> ComplexField.initializer(offset) }
-    return NDBuffer(strides, buffer)
+    return BufferND(strides, buffer)
 }
 
 

kmath-core/api/kmath-core.api

@@ -584,7 +584,6 @@ public final class space/kscience/kmath/linear/MatrixFeaturesKt {
 
 public final class space/kscience/kmath/linear/MatrixWrapper : space/kscience/kmath/nd/Structure2D {
 	public fun elements ()Lkotlin/sequences/Sequence;
-	public fun equals (Ljava/lang/Object;)Z
 	public fun get (II)Ljava/lang/Object;
 	public fun get ([I)Ljava/lang/Object;
 	public fun getColNum ()I
@@ -595,7 +594,6 @@ public final class space/kscience/kmath/linear/MatrixWrapper : space/kscience/km
 	public fun getRowNum ()I
 	public fun getRows ()Ljava/util/List;
 	public fun getShape ()[I
-	public fun hashCode ()I
 	public fun toString ()Ljava/lang/String;
 }
 
@@ -640,7 +638,6 @@ public final class space/kscience/kmath/linear/UnitFeature : space/kscience/kmat
 public final class space/kscience/kmath/linear/VirtualMatrix : space/kscience/kmath/nd/Structure2D {
 	public fun <init> (IILkotlin/jvm/functions/Function2;)V
 	public fun elements ()Lkotlin/sequences/Sequence;
-	public fun equals (Ljava/lang/Object;)Z
 	public fun get (II)Ljava/lang/Object;
 	public fun get ([I)Ljava/lang/Object;
 	public fun getColNum ()I
@@ -650,7 +647,6 @@ public final class space/kscience/kmath/linear/VirtualMatrix : space/kscience/km
 	public fun getRowNum ()I
 	public fun getRows ()Ljava/util/List;
 	public fun getShape ()[I
-	public fun hashCode ()I
 }
 
 public final class space/kscience/kmath/linear/ZeroFeature : space/kscience/kmath/linear/DiagonalFeature {
@@ -698,22 +694,22 @@ public final class space/kscience/kmath/nd/AlgebraND$DefaultImpls {
 }
 
 public abstract interface class space/kscience/kmath/nd/BufferAlgebraND : space/kscience/kmath/nd/AlgebraND {
-	public abstract fun combine (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/NDBuffer;
+	public abstract fun combine (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/BufferND;
 	public abstract fun getBuffer (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/structures/Buffer;
 	public abstract fun getBufferFactory ()Lkotlin/jvm/functions/Function2;
 	public abstract fun getStrides ()Lspace/kscience/kmath/nd/Strides;
-	public abstract fun map (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/NDBuffer;
+	public abstract fun map (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/BufferND;
-	public abstract fun mapIndexed (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/NDBuffer;
+	public abstract fun mapIndexed (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/BufferND;
-	public abstract fun produce (Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/NDBuffer;
+	public abstract fun produce (Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/BufferND;
 }
 
 public final class space/kscience/kmath/nd/BufferAlgebraND$DefaultImpls {
-	public static fun combine (Lspace/kscience/kmath/nd/BufferAlgebraND;Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/NDBuffer;
+	public static fun combine (Lspace/kscience/kmath/nd/BufferAlgebraND;Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/BufferND;
 	public static fun getBuffer (Lspace/kscience/kmath/nd/BufferAlgebraND;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/structures/Buffer;
 	public static fun invoke (Lspace/kscience/kmath/nd/BufferAlgebraND;Lkotlin/jvm/functions/Function1;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
-	public static fun map (Lspace/kscience/kmath/nd/BufferAlgebraND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/NDBuffer;
+	public static fun map (Lspace/kscience/kmath/nd/BufferAlgebraND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/BufferND;
-	public static fun mapIndexed (Lspace/kscience/kmath/nd/BufferAlgebraND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/NDBuffer;
+	public static fun mapIndexed (Lspace/kscience/kmath/nd/BufferAlgebraND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/BufferND;
-	public static fun produce (Lspace/kscience/kmath/nd/BufferAlgebraND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/NDBuffer;
+	public static fun produce (Lspace/kscience/kmath/nd/BufferAlgebraND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/BufferND;
 }
 
 public final class space/kscience/kmath/nd/BufferAlgebraNDKt {
@@ -725,6 +721,17 @@ public final class space/kscience/kmath/nd/BufferAlgebraNDKt {
 	public static final fun ring (Lspace/kscience/kmath/nd/AlgebraND$Companion;Lspace/kscience/kmath/operations/Ring;Lkotlin/jvm/functions/Function2;[I)Lspace/kscience/kmath/nd/BufferedRingND;
 }
 
+public class space/kscience/kmath/nd/BufferND : space/kscience/kmath/nd/StructureND {
+	public fun <init> (Lspace/kscience/kmath/nd/Strides;Lspace/kscience/kmath/structures/Buffer;)V
+	public fun elements ()Lkotlin/sequences/Sequence;
+	public fun get ([I)Ljava/lang/Object;
+	public fun getBuffer ()Lspace/kscience/kmath/structures/Buffer;
+	public fun getDimension ()I
+	public fun getShape ()[I
+	public final fun getStrides ()Lspace/kscience/kmath/nd/Strides;
+	public fun toString ()Ljava/lang/String;
+}
+
 public class space/kscience/kmath/nd/BufferedFieldND : space/kscience/kmath/nd/BufferedRingND, space/kscience/kmath/nd/FieldND {
 	public fun <init> ([ILspace/kscience/kmath/operations/Field;Lkotlin/jvm/functions/Function2;)V
 	public fun binaryOperationFunction (Ljava/lang/String;)Lkotlin/jvm/functions/Function2;
@@ -761,7 +768,7 @@ public class space/kscience/kmath/nd/BufferedGroupND : space/kscience/kmath/nd/B
 	public fun binaryOperationFunction (Ljava/lang/String;)Lkotlin/jvm/functions/Function2;
 	public synthetic fun bindSymbol (Ljava/lang/String;)Ljava/lang/Object;
 	public fun bindSymbol (Ljava/lang/String;)Lspace/kscience/kmath/nd/StructureND;
-	public fun combine (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun combine (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun combine (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/StructureND;
 	public fun getBuffer (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/structures/Buffer;
 	public final fun getBufferFactory ()Lkotlin/jvm/functions/Function2;
@@ -770,11 +777,11 @@ public class space/kscience/kmath/nd/BufferedGroupND : space/kscience/kmath/nd/B
 	public final fun getShape ()[I
 	public fun getStrides ()Lspace/kscience/kmath/nd/Strides;
 	public synthetic fun getZero ()Ljava/lang/Object;
-	public fun getZero ()Lspace/kscience/kmath/nd/NDBuffer;
+	public fun getZero ()Lspace/kscience/kmath/nd/BufferND;
 	public fun invoke (Lkotlin/jvm/functions/Function1;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
-	public fun map (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun map (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun map (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/StructureND;
-	public fun mapIndexed (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun mapIndexed (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun mapIndexed (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun minus (Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
 	public fun minus (Ljava/lang/Object;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
@@ -784,7 +791,7 @@ public class space/kscience/kmath/nd/BufferedGroupND : space/kscience/kmath/nd/B
 	public fun plus (Ljava/lang/Object;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
 	public fun plus (Lspace/kscience/kmath/nd/StructureND;Ljava/lang/Object;)Lspace/kscience/kmath/nd/StructureND;
 	public fun plus (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
-	public fun produce (Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun produce (Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun produce (Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun unaryMinus (Ljava/lang/Object;)Ljava/lang/Object;
 	public fun unaryMinus (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
@@ -799,7 +806,7 @@ public class space/kscience/kmath/nd/BufferedRingND : space/kscience/kmath/nd/Bu
 	public fun <init> ([ILspace/kscience/kmath/operations/Ring;Lkotlin/jvm/functions/Function2;)V
 	public fun binaryOperationFunction (Ljava/lang/String;)Lkotlin/jvm/functions/Function2;
 	public synthetic fun getOne ()Ljava/lang/Object;
-	public fun getOne ()Lspace/kscience/kmath/nd/NDBuffer;
+	public fun getOne ()Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun multiply (Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
 	public fun multiply (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun times (Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
@@ -828,43 +835,43 @@ public final class space/kscience/kmath/nd/DefaultStrides$Companion {
 public final class space/kscience/kmath/nd/DoubleFieldND : space/kscience/kmath/nd/BufferedFieldND, space/kscience/kmath/operations/ExtendedField, space/kscience/kmath/operations/NumbersAddOperations, space/kscience/kmath/operations/ScaleOperations {
 	public fun <init> ([I)V
 	public synthetic fun acos (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun acos (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun acos (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun acosh (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun acosh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun acosh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun asin (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun asin (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun asin (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun asinh (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun asinh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun asinh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun atan (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun atan (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun atan (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun atanh (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun atanh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun atanh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
-	public fun combine (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun combine (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun combine (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun cos (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun cos (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun cos (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun cosh (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun cosh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun cosh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun exp (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun exp (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun exp (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun getBuffer (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/structures/Buffer;
 	public fun getBuffer-Udx-57Q (Lspace/kscience/kmath/nd/StructureND;)[D
 	public synthetic fun getOne ()Ljava/lang/Object;
-	public fun getOne ()Lspace/kscience/kmath/nd/NDBuffer;
+	public fun getOne ()Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun getZero ()Ljava/lang/Object;
-	public fun getZero ()Lspace/kscience/kmath/nd/NDBuffer;
+	public fun getZero ()Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun ln (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun ln (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun ln (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
-	public fun map (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun map (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun map (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/StructureND;
-	public fun mapIndexed (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun mapIndexed (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun mapIndexed (Lspace/kscience/kmath/nd/StructureND;Lkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun minus (Ljava/lang/Number;Ljava/lang/Object;)Ljava/lang/Object;
 	public fun minus (Ljava/lang/Number;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun minus (Ljava/lang/Object;Ljava/lang/Number;)Ljava/lang/Object;
 	public fun minus (Lspace/kscience/kmath/nd/StructureND;Ljava/lang/Number;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun number (Ljava/lang/Number;)Ljava/lang/Object;
-	public fun number (Ljava/lang/Number;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun number (Ljava/lang/Number;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun number (Ljava/lang/Number;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun plus (Ljava/lang/Number;Ljava/lang/Object;)Ljava/lang/Object;
 	public fun plus (Ljava/lang/Number;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
@@ -873,22 +880,22 @@ public final class space/kscience/kmath/nd/DoubleFieldND : space/kscience/kmath/
 	public synthetic fun pow (Ljava/lang/Object;Ljava/lang/Number;)Ljava/lang/Object;
 	public fun pow (Lspace/kscience/kmath/nd/StructureND;Ljava/lang/Number;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun power (Ljava/lang/Object;Ljava/lang/Number;)Ljava/lang/Object;
-	public fun power (Lspace/kscience/kmath/nd/StructureND;Ljava/lang/Number;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun power (Lspace/kscience/kmath/nd/StructureND;Ljava/lang/Number;)Lspace/kscience/kmath/nd/BufferND;
-	public fun produce (Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun produce (Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun produce (Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/StructureND;
 	public fun rightSideNumberOperationFunction (Ljava/lang/String;)Lkotlin/jvm/functions/Function2;
 	public synthetic fun scale (Ljava/lang/Object;D)Ljava/lang/Object;
 	public fun scale (Lspace/kscience/kmath/nd/StructureND;D)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun sin (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun sin (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun sin (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun sinh (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun sinh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun sinh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun sqrt (Ljava/lang/Object;)Ljava/lang/Object;
 	public fun sqrt (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun tan (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun tan (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun tan (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun tanh (Ljava/lang/Object;)Ljava/lang/Object;
-	public fun tanh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun tanh (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/BufferND;
 	public fun unaryOperationFunction (Ljava/lang/String;)Lkotlin/jvm/functions/Function1;
 }
 
@@ -965,32 +972,19 @@ public final class space/kscience/kmath/nd/GroupND$DefaultImpls {
 	public static fun unaryPlus (Lspace/kscience/kmath/nd/GroupND;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
 }
 
-public final class space/kscience/kmath/nd/MutableNDBuffer : space/kscience/kmath/nd/NDBuffer, space/kscience/kmath/nd/MutableNDStructure {
+public final class space/kscience/kmath/nd/MutableBufferND : space/kscience/kmath/nd/BufferND, space/kscience/kmath/nd/MutableStructureND {
 	public fun <init> (Lspace/kscience/kmath/nd/Strides;Lspace/kscience/kmath/structures/MutableBuffer;)V
 	public synthetic fun getBuffer ()Lspace/kscience/kmath/structures/Buffer;
 	public fun getBuffer ()Lspace/kscience/kmath/structures/MutableBuffer;
 	public fun set ([ILjava/lang/Object;)V
 }
 
-public abstract interface class space/kscience/kmath/nd/MutableNDStructure : space/kscience/kmath/nd/StructureND {
+public abstract interface class space/kscience/kmath/nd/MutableStructureND : space/kscience/kmath/nd/StructureND {
 	public abstract fun set ([ILjava/lang/Object;)V
 }
 
-public final class space/kscience/kmath/nd/MutableNDStructure$DefaultImpls {
+public final class space/kscience/kmath/nd/MutableStructureND$DefaultImpls {
-	public static fun getDimension (Lspace/kscience/kmath/nd/MutableNDStructure;)I
+	public static fun getDimension (Lspace/kscience/kmath/nd/MutableStructureND;)I
-}
-
-public class space/kscience/kmath/nd/NDBuffer : space/kscience/kmath/nd/StructureND {
-	public fun <init> (Lspace/kscience/kmath/nd/Strides;Lspace/kscience/kmath/structures/Buffer;)V
-	public fun elements ()Lkotlin/sequences/Sequence;
-	public fun equals (Ljava/lang/Object;)Z
-	public fun get ([I)Ljava/lang/Object;
-	public fun getBuffer ()Lspace/kscience/kmath/structures/Buffer;
-	public fun getDimension ()I
-	public fun getShape ()[I
-	public final fun getStrides ()Lspace/kscience/kmath/nd/Strides;
-	public fun hashCode ()I
-	public fun toString ()Ljava/lang/String;
 }
 
 public abstract interface class space/kscience/kmath/nd/RingND : space/kscience/kmath/nd/GroupND, space/kscience/kmath/operations/Ring {
@@ -1033,9 +1027,9 @@ public final class space/kscience/kmath/nd/ShapeMismatchException : java/lang/Ru
 public final class space/kscience/kmath/nd/ShortRingND : space/kscience/kmath/nd/BufferedRingND, space/kscience/kmath/operations/NumbersAddOperations {
 	public fun <init> ([I)V
 	public synthetic fun getOne ()Ljava/lang/Object;
-	public fun getOne ()Lspace/kscience/kmath/nd/NDBuffer;
+	public fun getOne ()Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun getZero ()Ljava/lang/Object;
-	public fun getZero ()Lspace/kscience/kmath/nd/NDBuffer;
+	public fun getZero ()Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun leftSideNumberOperation (Ljava/lang/String;Ljava/lang/Number;Ljava/lang/Object;)Ljava/lang/Object;
 	public fun leftSideNumberOperation (Ljava/lang/String;Ljava/lang/Number;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
 	public fun leftSideNumberOperationFunction (Ljava/lang/String;)Lkotlin/jvm/functions/Function2;
@@ -1044,7 +1038,7 @@ public final class space/kscience/kmath/nd/ShortRingND : space/kscience/kmath/nd
 	public synthetic fun minus (Ljava/lang/Object;Ljava/lang/Number;)Ljava/lang/Object;
 	public fun minus (Lspace/kscience/kmath/nd/StructureND;Ljava/lang/Number;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun number (Ljava/lang/Number;)Ljava/lang/Object;
-	public fun number (Ljava/lang/Number;)Lspace/kscience/kmath/nd/NDBuffer;
+	public fun number (Ljava/lang/Number;)Lspace/kscience/kmath/nd/BufferND;
 	public synthetic fun plus (Ljava/lang/Number;Ljava/lang/Object;)Ljava/lang/Object;
 	public fun plus (Ljava/lang/Number;Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
 	public synthetic fun plus (Ljava/lang/Object;Ljava/lang/Number;)Ljava/lang/Object;
@@ -1056,7 +1050,7 @@ public final class space/kscience/kmath/nd/ShortRingND : space/kscience/kmath/nd
 
 public final class space/kscience/kmath/nd/ShortRingNDKt {
 	public static final fun nd (Lspace/kscience/kmath/operations/ShortRing;[ILkotlin/jvm/functions/Function1;)Ljava/lang/Object;
-	public static final fun produceInline (Lspace/kscience/kmath/nd/BufferedRingND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/NDBuffer;
+	public static final fun produceInline (Lspace/kscience/kmath/nd/BufferedRingND;Lkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/nd/BufferND;
 }
 
 public abstract interface class space/kscience/kmath/nd/Strides {
@@ -1121,20 +1115,18 @@ public final class space/kscience/kmath/nd/Structure2DKt {
 public abstract interface class space/kscience/kmath/nd/StructureND {
 	public static final field Companion Lspace/kscience/kmath/nd/StructureND$Companion;
 	public abstract fun elements ()Lkotlin/sequences/Sequence;
-	public abstract fun equals (Ljava/lang/Object;)Z
 	public abstract fun get ([I)Ljava/lang/Object;
 	public abstract fun getDimension ()I
 	public abstract fun getShape ()[I
-	public abstract fun hashCode ()I
 }
 
 public final class space/kscience/kmath/nd/StructureND$Companion {
-	public final fun auto (Lkotlin/reflect/KClass;Lspace/kscience/kmath/nd/Strides;Lkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/nd/NDBuffer;
+	public final fun auto (Lkotlin/reflect/KClass;Lspace/kscience/kmath/nd/Strides;Lkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/nd/BufferND;
-	public final fun auto (Lkotlin/reflect/KClass;[ILkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/nd/NDBuffer;
+	public final fun auto (Lkotlin/reflect/KClass;[ILkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/nd/BufferND;
-	public final fun buffered (Lspace/kscience/kmath/nd/Strides;Lkotlin/jvm/functions/Function2;Lkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/nd/NDBuffer;
+	public final fun buffered (Lspace/kscience/kmath/nd/Strides;Lkotlin/jvm/functions/Function2;Lkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/nd/BufferND;
-	public final fun buffered ([ILkotlin/jvm/functions/Function2;Lkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/nd/NDBuffer;
+	public final fun buffered ([ILkotlin/jvm/functions/Function2;Lkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/nd/BufferND;
-	public static synthetic fun buffered$default (Lspace/kscience/kmath/nd/StructureND$Companion;Lspace/kscience/kmath/nd/Strides;Lkotlin/jvm/functions/Function2;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)Lspace/kscience/kmath/nd/NDBuffer;
+	public static synthetic fun buffered$default (Lspace/kscience/kmath/nd/StructureND$Companion;Lspace/kscience/kmath/nd/Strides;Lkotlin/jvm/functions/Function2;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)Lspace/kscience/kmath/nd/BufferND;
-	public static synthetic fun buffered$default (Lspace/kscience/kmath/nd/StructureND$Companion;[ILkotlin/jvm/functions/Function2;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)Lspace/kscience/kmath/nd/NDBuffer;
+	public static synthetic fun buffered$default (Lspace/kscience/kmath/nd/StructureND$Companion;[ILkotlin/jvm/functions/Function2;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)Lspace/kscience/kmath/nd/BufferND;
 	public final fun contentEquals (Lspace/kscience/kmath/nd/StructureND;Lspace/kscience/kmath/nd/StructureND;)Z
 }
 
@@ -1144,7 +1136,7 @@ public final class space/kscience/kmath/nd/StructureND$DefaultImpls {
 
 public final class space/kscience/kmath/nd/StructureNDKt {
 	public static final fun get (Lspace/kscience/kmath/nd/StructureND;[I)Ljava/lang/Object;
-	public static final fun mapInPlace (Lspace/kscience/kmath/nd/MutableNDStructure;Lkotlin/jvm/functions/Function2;)V
+	public static final fun mapInPlace (Lspace/kscience/kmath/nd/MutableStructureND;Lkotlin/jvm/functions/Function2;)V
 }
 
 public abstract interface class space/kscience/kmath/operations/Algebra {

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

@@ -23,8 +23,6 @@ public class MatrixWrapper<T : Any> internal constructor(
     override fun <T : Any> getFeature(type: KClass<T>): T? = features.singleOrNull { type.isInstance(it) } as? T
         ?: origin.getFeature(type)
 
-    override fun equals(other: Any?): Boolean = origin == other
-    override fun hashCode(): Int = origin.hashCode()
     override fun toString(): String {
         return "MatrixWrapper(matrix=$origin, features=$features)"
     }

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

@@ -1,7 +1,5 @@
 package space.kscience.kmath.linear
 
-import space.kscience.kmath.nd.StructureND
-
 /**
  * The matrix where each element is evaluated each time when is being accessed.
  *
@@ -16,17 +14,4 @@ public class VirtualMatrix<T : Any>(
     override val shape: IntArray get() = intArrayOf(rowNum, colNum)
 
     override operator fun get(i: Int, j: Int): T = generator(i, j)
-
-    override fun equals(other: Any?): Boolean {
-        if (this === other) return true
-        if (other !is StructureND<*>) return false
-        return StructureND.contentEquals(this, other)
-    }
-
-    override fun hashCode(): Int {
-        var result = rowNum
-        result = 31 * result + colNum
-        result = 31 * result + generator.hashCode()
-        return result
-    }
 }

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

@@ -10,7 +10,7 @@ public interface BufferAlgebraND<T, A : Algebra<T>> : AlgebraND<T, A> {
     public val strides: Strides
     public val bufferFactory: BufferFactory<T>
 
-    override fun produce(initializer: A.(IntArray) -> T): NDBuffer<T> = NDBuffer(
+    override fun produce(initializer: A.(IntArray) -> T): BufferND<T> = BufferND(
         strides,
         bufferFactory(strides.linearSize) { offset ->
             elementContext.initializer(strides.index(offset))
@@ -23,32 +23,32 @@ public interface BufferAlgebraND<T, A : Algebra<T>> : AlgebraND<T, A> {
                 this@BufferAlgebraND.shape,
                 shape
             )
-            this is NDBuffer && this.strides == this@BufferAlgebraND.strides -> this.buffer
+            this is BufferND && this.strides == this@BufferAlgebraND.strides -> this.buffer
             else -> bufferFactory(strides.linearSize) { offset -> get(strides.index(offset)) }
         }
 
-    override fun StructureND<T>.map(transform: A.(T) -> T): NDBuffer<T> {
+    override fun StructureND<T>.map(transform: A.(T) -> T): BufferND<T> {
         val buffer = bufferFactory(strides.linearSize) { offset ->
             elementContext.transform(buffer[offset])
         }
-        return NDBuffer(strides, buffer)
+        return BufferND(strides, buffer)
     }
 
-    override fun StructureND<T>.mapIndexed(transform: A.(index: IntArray, T) -> T): NDBuffer<T> {
+    override fun StructureND<T>.mapIndexed(transform: A.(index: IntArray, T) -> T): BufferND<T> {
         val buffer = bufferFactory(strides.linearSize) { offset ->
             elementContext.transform(
                 strides.index(offset),
                 buffer[offset]
             )
         }
-        return NDBuffer(strides, buffer)
+        return BufferND(strides, buffer)
     }
 
-    override fun combine(a: StructureND<T>, b: StructureND<T>, transform: A.(T, T) -> T): NDBuffer<T> {
+    override fun combine(a: StructureND<T>, b: StructureND<T>, transform: A.(T, T) -> T): BufferND<T> {
         val buffer = bufferFactory(strides.linearSize) { offset ->
             elementContext.transform(a.buffer[offset], b.buffer[offset])
         }
-        return NDBuffer(strides, buffer)
+        return BufferND(strides, buffer)
     }
 }
 
@@ -58,7 +58,7 @@ public open class BufferedGroupND<T, A : Group<T>>(
     final override val bufferFactory: BufferFactory<T>,
 ) : GroupND<T, A>, BufferAlgebraND<T, A> {
     override val strides: Strides = DefaultStrides(shape)
-    override val zero: NDBuffer<T> by lazy { produce { zero } }
+    override val zero: BufferND<T> by lazy { produce { zero } }
     override fun StructureND<T>.unaryMinus(): StructureND<T> = produce { -get(it) }
 }
 
@@ -67,7 +67,7 @@ public open class BufferedRingND<T, R : Ring<T>>(
     elementContext: R,
     bufferFactory: BufferFactory<T>,
 ) : BufferedGroupND<T, R>(shape, elementContext, bufferFactory), RingND<T, R> {
-    override val one: NDBuffer<T> by lazy { produce { one } }
+    override val one: BufferND<T> by lazy { produce { one } }
 }
 
 public open class BufferedFieldND<T, R : Field<T>>(

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

@@ -17,10 +17,10 @@ public class DoubleFieldND(
     ScaleOperations<StructureND<Double>>,
     ExtendedField<StructureND<Double>> {
 
-    override val zero: NDBuffer<Double> by lazy { produce { zero } }
+    override val zero: BufferND<Double> by lazy { produce { zero } }
-    override val one: NDBuffer<Double> by lazy { produce { one } }
+    override val one: BufferND<Double> by lazy { produce { one } }
 
-    override fun number(value: Number): NDBuffer<Double> {
+    override fun number(value: Number): BufferND<Double> {
         val d = value.toDouble() // minimize conversions
         return produce { d }
     }
@@ -31,31 +31,31 @@ public class DoubleFieldND(
                 this@DoubleFieldND.shape,
                 shape
             )
-            this is NDBuffer && this.strides == this@DoubleFieldND.strides -> this.buffer as DoubleBuffer
+            this is BufferND && this.strides == this@DoubleFieldND.strides -> this.buffer as DoubleBuffer
             else -> DoubleBuffer(strides.linearSize) { offset -> get(strides.index(offset)) }
         }
 
     @Suppress("OVERRIDE_BY_INLINE")
     override inline fun StructureND<Double>.map(
         transform: DoubleField.(Double) -> Double,
-    ): NDBuffer<Double> {
+    ): BufferND<Double> {
         val buffer = DoubleBuffer(strides.linearSize) { offset -> DoubleField.transform(buffer.array[offset]) }
-        return NDBuffer(strides, buffer)
+        return BufferND(strides, buffer)
     }
 
     @Suppress("OVERRIDE_BY_INLINE")
-    override inline fun produce(initializer: DoubleField.(IntArray) -> Double): NDBuffer<Double> {
+    override inline fun produce(initializer: DoubleField.(IntArray) -> Double): BufferND<Double> {
         val array = DoubleArray(strides.linearSize) { offset ->
             val index = strides.index(offset)
             DoubleField.initializer(index)
         }
-        return NDBuffer(strides, DoubleBuffer(array))
+        return BufferND(strides, DoubleBuffer(array))
     }
 
     @Suppress("OVERRIDE_BY_INLINE")
     override inline fun StructureND<Double>.mapIndexed(
         transform: DoubleField.(index: IntArray, Double) -> Double,
-    ): NDBuffer<Double> = NDBuffer(
+    ): BufferND<Double> = BufferND(
         strides,
         buffer = DoubleBuffer(strides.linearSize) { offset ->
             DoubleField.transform(
@@ -69,34 +69,34 @@ public class DoubleFieldND(
         a: StructureND<Double>,
         b: StructureND<Double>,
         transform: DoubleField.(Double, Double) -> Double,
-    ): NDBuffer<Double> {
+    ): BufferND<Double> {
         val buffer = DoubleBuffer(strides.linearSize) { offset ->
             DoubleField.transform(a.buffer.array[offset], b.buffer.array[offset])
         }
-        return NDBuffer(strides, buffer)
+        return BufferND(strides, buffer)
     }
 
     override fun scale(a: StructureND<Double>, value: Double): StructureND<Double> = a.map { it * value }
 
-    override fun power(arg: StructureND<Double>, pow: Number): NDBuffer<Double> = arg.map { power(it, pow) }
+    override fun power(arg: StructureND<Double>, pow: Number): BufferND<Double> = arg.map { power(it, pow) }
 
-    override fun exp(arg: StructureND<Double>): NDBuffer<Double> = arg.map { exp(it) }
+    override fun exp(arg: StructureND<Double>): BufferND<Double> = arg.map { exp(it) }
 
-    override fun ln(arg: StructureND<Double>): NDBuffer<Double> = arg.map { ln(it) }
+    override fun ln(arg: StructureND<Double>): BufferND<Double> = arg.map { ln(it) }
 
-    override fun sin(arg: StructureND<Double>): NDBuffer<Double> = arg.map { sin(it) }
+    override fun sin(arg: StructureND<Double>): BufferND<Double> = arg.map { sin(it) }
-    override fun cos(arg: StructureND<Double>): NDBuffer<Double> = arg.map { cos(it) }
+    override fun cos(arg: StructureND<Double>): BufferND<Double> = arg.map { cos(it) }
-    override fun tan(arg: StructureND<Double>): NDBuffer<Double> = arg.map { tan(it) }
+    override fun tan(arg: StructureND<Double>): BufferND<Double> = arg.map { tan(it) }
-    override fun asin(arg: StructureND<Double>): NDBuffer<Double> = arg.map { asin(it) }
+    override fun asin(arg: StructureND<Double>): BufferND<Double> = arg.map { asin(it) }
-    override fun acos(arg: StructureND<Double>): NDBuffer<Double> = arg.map { acos(it) }
+    override fun acos(arg: StructureND<Double>): BufferND<Double> = arg.map { acos(it) }
-    override fun atan(arg: StructureND<Double>): NDBuffer<Double> = arg.map { atan(it) }
+    override fun atan(arg: StructureND<Double>): BufferND<Double> = arg.map { atan(it) }
 
-    override fun sinh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { sinh(it) }
+    override fun sinh(arg: StructureND<Double>): BufferND<Double> = arg.map { sinh(it) }
-    override fun cosh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { cosh(it) }
+    override fun cosh(arg: StructureND<Double>): BufferND<Double> = arg.map { cosh(it) }
-    override fun tanh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { tanh(it) }
+    override fun tanh(arg: StructureND<Double>): BufferND<Double> = arg.map { tanh(it) }
-    override fun asinh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { asinh(it) }
+    override fun asinh(arg: StructureND<Double>): BufferND<Double> = arg.map { asinh(it) }
-    override fun acosh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { acosh(it) }
+    override fun acosh(arg: StructureND<Double>): BufferND<Double> = arg.map { acosh(it) }
-    override fun atanh(arg: StructureND<Double>): NDBuffer<Double> = arg.map { atanh(it) }
+    override fun atanh(arg: StructureND<Double>): BufferND<Double> = arg.map { atanh(it) }
 }
 
 public fun AlgebraND.Companion.real(vararg shape: Int): DoubleFieldND = DoubleFieldND(shape)

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

@@ -14,10 +14,10 @@ public class ShortRingND(
 ) : BufferedRingND<Short, ShortRing>(shape, ShortRing, Buffer.Companion::auto),
     NumbersAddOperations<StructureND<Short>> {
 
-    override val zero: NDBuffer<Short> by lazy { produce { zero } }
+    override val zero: BufferND<Short> by lazy { produce { zero } }
-    override val one: NDBuffer<Short> by lazy { produce { one } }
+    override val one: BufferND<Short> by lazy { produce { one } }
 
-    override fun number(value: Number): NDBuffer<Short> {
+    override fun number(value: Number): BufferND<Short> {
         val d = value.toShort() // minimize conversions
         return produce { d }
     }
@@ -26,8 +26,8 @@ public class ShortRingND(
 /**
  * Fast element production using function inlining.
  */
-public inline fun BufferedRingND<Short, ShortRing>.produceInline(crossinline initializer: ShortRing.(Int) -> Short): NDBuffer<Short> {
+public inline fun BufferedRingND<Short, ShortRing>.produceInline(crossinline initializer: ShortRing.(Int) -> Short): BufferND<Short> {
-    return NDBuffer(strides, ShortBuffer(ShortArray(strides.linearSize) { offset -> ShortRing.initializer(offset) }))
+    return BufferND(strides, ShortBuffer(ShortArray(strides.linearSize) { offset -> ShortRing.initializer(offset) }))
 }
 
 public inline fun <R> ShortRing.nd(vararg shape: Int, action: ShortRingND.() -> R): R {

kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/Structure1D.kt

@@ -47,7 +47,7 @@ private inline class Buffer1DWrapper<T>(val buffer: Buffer<T>) : Structure1D<T>
  */
 public fun <T> StructureND<T>.as1D(): Structure1D<T> = this as? Structure1D<T> ?: if (shape.size == 1) {
     when (this) {
-        is NDBuffer -> Buffer1DWrapper(this.buffer)
+        is BufferND -> Buffer1DWrapper(this.buffer)
         else -> Structure1DWrapper(this)
     }
 } else error("Can't create 1d-structure from ${shape.size}d-structure")
@@ -62,6 +62,6 @@ public fun <T> Buffer<T>.asND(): Structure1D<T> = Buffer1DWrapper(this)
  */
 internal fun <T : Any> Structure1D<T>.unwrap(): Buffer<T> = when {
     this is Buffer1DWrapper<T> -> buffer
-    this is Structure1DWrapper && structure is NDBuffer<T> -> structure.buffer
+    this is Structure1DWrapper && structure is BufferND<T> -> structure.buffer
     else -> this
 }

kmath-core/src/commonMain/kotlin/space/kscience/kmath/nd/Structure2D.kt

@@ -60,7 +60,7 @@ public interface Structure2D<T> : StructureND<T> {
 /**
  * A 2D wrapper for nd-structure
  */
-private class Structure2DWrapper<T>(val structure: StructureND<T>) : Structure2D<T> {
+private inline class Structure2DWrapper<T>(val structure: StructureND<T>) : Structure2D<T> {
     override val shape: IntArray get() = structure.shape
 
     override val rowNum: Int get() = shape[0]
@@ -72,10 +72,6 @@ private class Structure2DWrapper<T>(val structure: StructureND<T>) : Structure2D
     override fun <F : Any> getFeature(type: KClass<F>): F? = structure.getFeature(type)
 
     override fun elements(): Sequence<Pair<IntArray, T>> = structure.elements()
-
-    override fun equals(other: Any?): Boolean = structure == other
-
-    override fun hashCode(): Int = structure.hashCode()
 }
 
 /**

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

@@ -14,6 +14,8 @@ import kotlin.reflect.KClass
  * of dimensions and items in an array is defined by its shape, which is a sequence of non-negative integers that
  * specify the sizes of each dimension.
  *
+ * StructureND is in general identity-free. [StructureND.contentEquals] should be used in tests to compare contents.
+ *
  * @param T the type of items.
  */
 public interface StructureND<T> {
@@ -43,10 +45,6 @@ public interface StructureND<T> {
      */
     public fun elements(): Sequence<Pair<IntArray, T>>
 
-    //force override equality and hash code
-    public override fun equals(other: Any?): Boolean
-    public override fun hashCode(): Int
-
     /**
      * Feature is some additional strucure information which allows to access it special properties or hints.
      * If the feature is not present, null is returned.
@@ -62,7 +60,7 @@ public interface StructureND<T> {
             if (st1 === st2) return true
 
             // fast comparison of buffers if possible
-            if (st1 is NDBuffer && st2 is NDBuffer && st1.strides == st2.strides)
+            if (st1 is BufferND && st2 is BufferND && st1.strides == st2.strides)
                 return st1.buffer.contentEquals(st2.buffer)
 
             //element by element comparison if it could not be avoided
@@ -78,7 +76,7 @@ public interface StructureND<T> {
             strides: Strides,
             bufferFactory: BufferFactory<T> = Buffer.Companion::boxing,
             initializer: (IntArray) -> T,
-        ): NDBuffer<T> = NDBuffer(strides, bufferFactory(strides.linearSize) { i -> initializer(strides.index(i)) })
+        ): BufferND<T> = BufferND(strides, bufferFactory(strides.linearSize) { i -> initializer(strides.index(i)) })
 
         /**
          * Inline create NDStructure with non-boxing buffer implementation if it is possible
@@ -86,37 +84,37 @@ public interface StructureND<T> {
         public inline fun <reified T : Any> auto(
             strides: Strides,
             crossinline initializer: (IntArray) -> T,
-        ): NDBuffer<T> = NDBuffer(strides, Buffer.auto(strides.linearSize) { i -> initializer(strides.index(i)) })
+        ): BufferND<T> = BufferND(strides, Buffer.auto(strides.linearSize) { i -> initializer(strides.index(i)) })
 
         public inline fun <T : Any> auto(
             type: KClass<T>,
             strides: Strides,
             crossinline initializer: (IntArray) -> T,
-        ): NDBuffer<T> = NDBuffer(strides, Buffer.auto(type, strides.linearSize) { i -> initializer(strides.index(i)) })
+        ): BufferND<T> = BufferND(strides, Buffer.auto(type, strides.linearSize) { i -> initializer(strides.index(i)) })
 
         public fun <T> buffered(
             shape: IntArray,
             bufferFactory: BufferFactory<T> = Buffer.Companion::boxing,
             initializer: (IntArray) -> T,
-        ): NDBuffer<T> = buffered(DefaultStrides(shape), bufferFactory, initializer)
+        ): BufferND<T> = buffered(DefaultStrides(shape), bufferFactory, initializer)
 
         public inline fun <reified T : Any> auto(
             shape: IntArray,
             crossinline initializer: (IntArray) -> T,
-        ): NDBuffer<T> = auto(DefaultStrides(shape), initializer)
+        ): BufferND<T> = auto(DefaultStrides(shape), initializer)
 
         @JvmName("autoVarArg")
         public inline fun <reified T : Any> auto(
             vararg shape: Int,
             crossinline initializer: (IntArray) -> T,
-        ): NDBuffer<T> =
+        ): BufferND<T> =
             auto(DefaultStrides(shape), initializer)
 
         public inline fun <T : Any> auto(
             type: KClass<T>,
             vararg shape: Int,
             crossinline initializer: (IntArray) -> T,
-        ): NDBuffer<T> = auto(type, DefaultStrides(shape), initializer)
+        ): BufferND<T> = auto(type, DefaultStrides(shape), initializer)
     }
 }
 
@@ -134,7 +132,7 @@ public inline fun <reified T : Any> StructureND<*>.getFeature(): T? = getFeature
 /**
  * Represents mutable [StructureND].
  */
-public interface MutableNDStructure<T> : StructureND<T> {
+public interface MutableStructureND<T> : StructureND<T> {
     /**
      * Inserts an item at the specified indices.
      *
@@ -147,7 +145,7 @@ public interface MutableNDStructure<T> : StructureND<T> {
 /**
  * Transform a structure element-by element in place.
  */
-public inline fun <T> MutableNDStructure<T>.mapInPlace(action: (IntArray, T) -> T): Unit =
+public inline fun <T> MutableStructureND<T>.mapInPlace(action: (IntArray, T) -> T): Unit =
     elements().forEach { (index, oldValue) -> this[index] = action(index, oldValue) }
 
 /**
@@ -258,7 +256,7 @@ public class DefaultStrides private constructor(override val shape: IntArray) :
  * @param strides The strides to access elements of [Buffer] by linear indices.
  * @param buffer The underlying buffer.
  */
-public open class NDBuffer<T>(
+public open class BufferND<T>(
     public val strides: Strides,
     buffer: Buffer<T>,
 ) : StructureND<T> {
@@ -279,16 +277,6 @@ public open class NDBuffer<T>(
         it to this[it]
     }
 
-    override fun equals(other: Any?): Boolean {
-        return StructureND.contentEquals(this, other as? StructureND<*> ?: return false)
-    }
-
-    override fun hashCode(): Int {
-        var result = strides.hashCode()
-        result = 31 * result + buffer.hashCode()
-        return result
-    }
-
     override fun toString(): String {
         val bufferRepr: String = when (shape.size) {
             1 -> buffer.asSequence().joinToString(prefix = "[", postfix = "]", separator = ", ")
@@ -305,27 +293,27 @@ public open class NDBuffer<T>(
 }
 
 /**
- * Transform structure to a new structure using provided [BufferFactory] and optimizing if argument is [NDBuffer]
+ * Transform structure to a new structure using provided [BufferFactory] and optimizing if argument is [BufferND]
  */
 public inline fun <T, reified R : Any> StructureND<T>.mapToBuffer(
     factory: BufferFactory<R> = Buffer.Companion::auto,
     crossinline transform: (T) -> R,
-): NDBuffer<R> {
+): BufferND<R> {
-    return if (this is NDBuffer<T>)
+    return if (this is BufferND<T>)
-        NDBuffer(this.strides, factory.invoke(strides.linearSize) { transform(buffer[it]) })
+        BufferND(this.strides, factory.invoke(strides.linearSize) { transform(buffer[it]) })
     else {
         val strides = DefaultStrides(shape)
-        NDBuffer(strides, factory.invoke(strides.linearSize) { transform(get(strides.index(it))) })
+        BufferND(strides, factory.invoke(strides.linearSize) { transform(get(strides.index(it))) })
     }
 }
 
 /**
  * Mutable ND buffer based on linear [MutableBuffer].
  */
-public class MutableNDBuffer<T>(
+public class MutableBufferND<T>(
     strides: Strides,
     buffer: MutableBuffer<T>,
-) : NDBuffer<T>(strides, buffer), MutableNDStructure<T> {
+) : BufferND<T>(strides, buffer), MutableStructureND<T> {
 
     init {
         require(strides.linearSize == buffer.size) {

kmath-core/src/commonMain/kotlin/space/kscience/kmath/structures/Buffer.kt

@@ -17,7 +17,9 @@ public typealias BufferFactory<T> = (Int, (Int) -> T) -> Buffer<T>
 public typealias MutableBufferFactory<T> = (Int, (Int) -> T) -> MutableBuffer<T>
 
 /**
- * A generic immutable random-access structure for both primitives and objects.
+ * A generic read-only random-access structure for both primitives and objects.
+ *
+ * [Buffer] is in general identity-free. [contentEquals] should be used for content equality checks
  *
  * @param T the type of elements contained in the buffer.
  */
@@ -40,8 +42,13 @@ public interface Buffer<out T> {
     /**
      * Checks content equality with another buffer.
      */
-    public fun contentEquals(other: Buffer<*>): Boolean =
+    public fun contentEquals(other: Buffer<*>): Boolean {
-        asSequence().mapIndexed { index, value -> value == other[index] }.all { it }
+        if (this.size != other.size) return false
+        for (i in indices) {
+            if (get(i) != other[i]) return false
+        }
+        return true
+    }
 
     public companion object {
         /**

kmath-core/src/commonTest/kotlin/space/kscience/kmath/linear/DoubleLUSolverTest.kt

@@ -1,8 +1,14 @@
 package space.kscience.kmath.linear
 
 import space.kscience.kmath.misc.UnstableKMathAPI
+import space.kscience.kmath.nd.StructureND
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertTrue
+
+fun <T : Any> assertMatrixEquals(expected: StructureND<T>, actual: StructureND<T>) {
+    assertTrue { StructureND.contentEquals(expected, actual) }
+}
 
 @UnstableKMathAPI
 class DoubleLUSolverTest {
@@ -11,7 +17,7 @@ class DoubleLUSolverTest {
     fun testInvertOne() {
         val matrix = LinearSpace.real.one(2, 2)
         val inverted = LinearSpace.real.inverseWithLup(matrix)
-        assertEquals(matrix, inverted)
+        assertMatrixEquals(matrix, inverted)
     }
 
     @Test
@@ -27,7 +33,7 @@ class DoubleLUSolverTest {
             //Check determinant
             assertEquals(7.0, lup.determinant)
 
-            assertEquals(lup.p dot matrix, lup.l dot lup.u)
+            assertMatrixEquals(lup.p dot matrix, lup.l dot lup.u)
         }
     }
 
@@ -45,6 +51,6 @@ class DoubleLUSolverTest {
             -0.125, 0.375
         )
 
-        assertEquals(expected, inverted)
+        assertMatrixEquals(expected, inverted)
     }
 }

kmath-core/src/commonTest/kotlin/space/kscience/kmath/linear/MatrixTest.kt

@@ -5,6 +5,7 @@ import space.kscience.kmath.nd.StructureND
 import space.kscience.kmath.nd.as2D
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertTrue
 
 @UnstableKMathAPI
 @Suppress("UNUSED_VARIABLE")
@@ -13,7 +14,7 @@ class MatrixTest {
     fun testTranspose() {
         val matrix = LinearSpace.real.one(3, 3)
         val transposed = matrix.transpose()
-        assertEquals(matrix, transposed)
+        assertTrue { StructureND.contentEquals(matrix, transposed) }
     }
 
     @Test

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

@@ -24,18 +24,6 @@ public class LazyStructureND<T>(
         val res = runBlocking { strides.indices().toList().map { index -> index to await(index) } }
         return res.asSequence()
     }
-
-    public override fun equals(other: Any?): Boolean {
-        return StructureND.contentEquals(this, other as? StructureND<*> ?: return false)
-    }
-
-    public override fun hashCode(): Int {
-        var result = scope.hashCode()
-        result = 31 * result + shape.contentHashCode()
-        result = 31 * result + function.hashCode()
-        result = 31 * result + cache.hashCode()
-        return result
-    }
 }
 
 public fun <T> StructureND<T>.deferred(index: IntArray): Deferred<T> =

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

@@ -2,7 +2,6 @@ package space.kscience.kmath.ejml
 
 import org.ejml.simple.SimpleMatrix
 import space.kscience.kmath.linear.Matrix
-import space.kscience.kmath.nd.StructureND
 
 /**
  * Represents featured matrix over EJML [SimpleMatrix].
@@ -10,19 +9,9 @@ import space.kscience.kmath.nd.StructureND
  * @property origin the underlying [SimpleMatrix].
  * @author Iaroslav Postovalov
  */
-public class EjmlMatrix(public val origin: SimpleMatrix) : Matrix<Double> {
+public inline class EjmlMatrix(public val origin: SimpleMatrix) : Matrix<Double> {
     public override val rowNum: Int get() = origin.numRows()
     public override val colNum: Int get() = origin.numCols()
 
     public override operator fun get(i: Int, j: Int): Double = origin[i, j]
-
-    override fun equals(other: Any?): Boolean {
-        if (this === other) return true
-        if (other !is StructureND<*>) return false
-        return StructureND.contentEquals(this, other)
-    }
-
-    override fun hashCode(): Int = origin.hashCode()
-
-
 }

kmath-ejml/src/test/kotlin/space/kscience/kmath/ejml/EjmlMatrixTest.kt

@@ -4,11 +4,16 @@ import org.ejml.dense.row.factory.DecompositionFactory_DDRM
 import org.ejml.simple.SimpleMatrix
 import space.kscience.kmath.linear.*
 import space.kscience.kmath.misc.UnstableKMathAPI
+import space.kscience.kmath.nd.StructureND
 import space.kscience.kmath.nd.getFeature
 import kotlin.random.Random
 import kotlin.random.asJavaRandom
 import kotlin.test.*
 
+fun <T : Any> assertMatrixEquals(expected: StructureND<T>, actual: StructureND<T>) {
+    assertTrue { StructureND.contentEquals(expected, actual) }
+}
+
 internal class EjmlMatrixTest {
     private val random = Random(0)
 
@@ -49,9 +54,9 @@ internal class EjmlMatrixTest {
         val ludecompositionF64 = DecompositionFactory_DDRM.lu(m.numRows(), m.numCols())
             .also { it.decompose(m.ddrm.copy()) }
 
-        assertEquals(EjmlMatrix(SimpleMatrix(ludecompositionF64.getLower(null))), lup.l)
+        assertMatrixEquals(EjmlMatrix(SimpleMatrix(ludecompositionF64.getLower(null))), lup.l)
-        assertEquals(EjmlMatrix(SimpleMatrix(ludecompositionF64.getUpper(null))), lup.u)
+        assertMatrixEquals(EjmlMatrix(SimpleMatrix(ludecompositionF64.getUpper(null))), lup.u)
-        assertEquals(EjmlMatrix(SimpleMatrix(ludecompositionF64.getRowPivot(null))), lup.p)
+        assertMatrixEquals(EjmlMatrix(SimpleMatrix(ludecompositionF64.getRowPivot(null))), lup.p)
     }
 
     private object SomeFeature : MatrixFeature {}

kmath-for-real/src/commonMain/kotlin/space/kscience/kmath/real/realND.kt

@@ -1,31 +1,31 @@
 package space.kscience.kmath.real
 
-import space.kscience.kmath.nd.NDBuffer
+import space.kscience.kmath.nd.BufferND
 import space.kscience.kmath.operations.DoubleField
 import space.kscience.kmath.structures.DoubleBuffer
 
 /**
- * Map one [NDBuffer] using function without indices.
+ * Map one [BufferND] using function without indices.
  */
-public inline fun NDBuffer<Double>.mapInline(crossinline transform: DoubleField.(Double) -> Double): NDBuffer<Double> {
+public inline fun BufferND<Double>.mapInline(crossinline transform: DoubleField.(Double) -> Double): BufferND<Double> {
     val array = DoubleArray(strides.linearSize) { offset -> DoubleField.transform(buffer[offset]) }
-    return NDBuffer(strides, DoubleBuffer(array))
+    return BufferND(strides, DoubleBuffer(array))
 }
 
 /**
  * Element by element application of any operation on elements to the whole array. Just like in numpy.
  */
-public operator fun Function1<Double, Double>.invoke(ndElement: NDBuffer<Double>): NDBuffer<Double> =
+public operator fun Function1<Double, Double>.invoke(elementND: BufferND<Double>): BufferND<Double> =
-    ndElement.mapInline { this@invoke(it) }
+    elementND.mapInline { this@invoke(it) }
 
 /* plus and minus */
 
 /**
- * Summation operation for [NDBuffer] and single element
+ * Summation operation for [BufferND] and single element
  */
-public operator fun NDBuffer<Double>.plus(arg: Double): NDBuffer<Double> = mapInline { it + arg }
+public operator fun BufferND<Double>.plus(arg: Double): BufferND<Double> = mapInline { it + arg }
 
 /**
- * Subtraction operation between [NDBuffer] and single element
+ * Subtraction operation between [BufferND] and single element
  */
-public operator fun NDBuffer<Double>.minus(arg: Double): NDBuffer<Double> = mapInline { it - arg }
+public operator fun BufferND<Double>.minus(arg: Double): BufferND<Double> = mapInline { it - arg }

kmath-for-real/src/commonTest/kotlin/kaceince/kmath/real/DoubleMatrixTest.kt

@@ -3,12 +3,17 @@ package kaceince.kmath.real
 import space.kscience.kmath.linear.LinearSpace
 import space.kscience.kmath.linear.matrix
 import space.kscience.kmath.misc.UnstableKMathAPI
+import space.kscience.kmath.nd.StructureND
 import space.kscience.kmath.real.*
 import space.kscience.kmath.structures.contentEquals
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertTrue
 
+fun <T : Any> assertMatrixEquals(expected: StructureND<T>, actual: StructureND<T>) {
+    assertTrue { StructureND.contentEquals(expected, actual) }
+}
+
 @UnstableKMathAPI
 internal class DoubleMatrixTest {
     @Test
@@ -43,7 +48,7 @@ internal class DoubleMatrixTest {
             1.0, 0.0, 0.0,
             0.0, 1.0, 2.0
         )
-        assertEquals(matrix2, matrix1.repeatStackVertical(3))
+        assertMatrixEquals(matrix2, matrix1.repeatStackVertical(3))
     }
 
     @Test
@@ -57,7 +62,7 @@ internal class DoubleMatrixTest {
             0.75, -0.5, 3.25,
             4.5, 7.0, 2.0
         )
-        assertEquals(matrix2, expectedResult)
+        assertMatrixEquals(matrix2, expectedResult)
     }
 
     @Test
@@ -72,7 +77,7 @@ internal class DoubleMatrixTest {
             5.0, 10.0, -5.0,
             -10.0, -20.0, 0.0
         )
-        assertEquals(matrix2, expectedResult)
+        assertMatrixEquals(matrix2, expectedResult)
     }
 
     @Test
@@ -89,8 +94,8 @@ internal class DoubleMatrixTest {
             -1.0, 0.0, 27.0,
             64.0, -216.0, -8.0
         )
-        assertEquals(matrix1.square(), matrix2)
+        assertMatrixEquals(matrix1.square(), matrix2)
-        assertEquals(matrix1.pow(3), matrix3)
+        assertMatrixEquals(matrix1.pow(3), matrix3)
     }
 
     @OptIn(UnstableKMathAPI::class)
@@ -109,7 +114,7 @@ internal class DoubleMatrixTest {
             -3.0, 0.0, 9.0,
             16.0, -48.0, -5.0
         )
-        assertEquals(result, expectedResult)
+        assertMatrixEquals(result, expectedResult)
     }
 
     @Test
@@ -128,9 +133,9 @@ internal class DoubleMatrixTest {
             -6.0, 7.0
         )
 
-        assertEquals(matrix1.appendColumn { it[0] }, matrix2)
+        assertMatrixEquals(matrix1.appendColumn { it[0] }, matrix2)
-        assertEquals(matrix1.extractColumn(1), col1)
+        assertMatrixEquals(matrix1.extractColumn(1), col1)
-        assertEquals(matrix1.extractColumns(1..2), cols1to2)
+        assertMatrixEquals(matrix1.extractColumns(1..2), cols1to2)
         //equals should never be called on buffers
         assertTrue {
             matrix1.sumByColumn().contentEquals(3.0, -6.0, 10.0, 4.0)

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

@@ -75,7 +75,7 @@ public class DoubleHistogramSpace(
             ndCounter[index].add(value.toDouble())
         }
         hBuilder.apply(builder)
-        val values: NDBuffer<Double> = ndCounter.mapToBuffer { it.value }
+        val values: BufferND<Double> = ndCounter.mapToBuffer { it.value }
         return IndexedHistogram(this, values)
     }
 

kmath-nd4j/src/main/kotlin/space/kscience/kmath/nd4j/Nd4jArrayStructure.kt

@@ -1,7 +1,7 @@
 package space.kscience.kmath.nd4j
 
 import org.nd4j.linalg.api.ndarray.INDArray
-import space.kscience.kmath.nd.MutableNDStructure
+import space.kscience.kmath.nd.MutableStructureND
 import space.kscience.kmath.nd.StructureND
 
 /**
@@ -9,7 +9,7 @@ import space.kscience.kmath.nd.StructureND
  *
  * @param T the type of items.
  */
-public sealed class Nd4jArrayStructure<T> : MutableNDStructure<T> {
+public sealed class Nd4jArrayStructure<T> : MutableStructureND<T> {
     /**
      * The wrapped [INDArray].
      */

kmath-viktor/api/kmath-viktor.api

@@ -148,7 +148,7 @@ public final class space/kscience/kmath/viktor/ViktorFieldND : space/kscience/km
 	public fun unaryPlus (Lspace/kscience/kmath/nd/StructureND;)Lspace/kscience/kmath/nd/StructureND;
 }
 
-public final class space/kscience/kmath/viktor/ViktorStructureND : space/kscience/kmath/nd/MutableNDStructure {
+public final class space/kscience/kmath/viktor/ViktorStructureND : space/kscience/kmath/nd/MutableStructureND {
 	public static final synthetic fun box-impl (Lorg/jetbrains/bio/viktor/F64Array;)Lspace/kscience/kmath/viktor/ViktorStructureND;
 	public static fun constructor-impl (Lorg/jetbrains/bio/viktor/F64Array;)Lorg/jetbrains/bio/viktor/F64Array;
 	public fun elements ()Lkotlin/sequences/Sequence;

kmath-viktor/src/main/kotlin/space/kscience/kmath/viktor/ViktorStructureND.kt

@@ -9,7 +9,7 @@ import space.kscience.kmath.operations.NumbersAddOperations
 import space.kscience.kmath.operations.ScaleOperations
 
 @Suppress("OVERRIDE_BY_INLINE", "NOTHING_TO_INLINE")
-public inline class ViktorStructureND(public val f64Buffer: F64Array) : MutableNDStructure<Double> {
+public inline class ViktorStructureND(public val f64Buffer: F64Array) : MutableStructureND<Double> {
     public override val shape: IntArray get() = f64Buffer.shape
 
     public override inline fun get(index: IntArray): Double = f64Buffer.get(*index)