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

@@ -8,7 +8,7 @@ package space.kscience.kmath.histogram
 import kotlinx.atomicfu.atomic
 import kotlinx.atomicfu.getAndUpdate
 import space.kscience.kmath.operations.DoubleField
-import space.kscience.kmath.operations.Ring
+import space.kscience.kmath.operations.Group
 
 /**
  * Common representation for atomic counters
@@ -18,7 +18,7 @@ public interface Counter<T : Any> {
     public val value: T
 
     public companion object {
-        public fun real(): ObjectCounter<Double> = ObjectCounter(DoubleField)
+        public fun double(): ObjectCounter<Double> = ObjectCounter(DoubleField)
     }
 }
 
@@ -32,6 +32,16 @@ public class IntCounter : Counter<Int> {
     override val value: Int get() = innerValue.value
 }
 
+public operator fun IntCounter.inc(): IntCounter {
+    add(1)
+    return this
+}
+
+public operator fun IntCounter.dec(): IntCounter {
+    add(-1)
+    return this
+}
+
 public class LongCounter : Counter<Long> {
     private val innerValue = atomic(0L)
 
@@ -42,7 +52,17 @@ public class LongCounter : Counter<Long> {
     override val value: Long get() = innerValue.value
 }
 
-public class ObjectCounter<T : Any>(public val group: Ring<T>) : Counter<T> {
+public operator fun LongCounter.inc(): LongCounter {
+    add(1L)
+    return this
+}
+
+public operator fun LongCounter.dec(): LongCounter {
+    add(-1L)
+    return this
+}
+
+public class ObjectCounter<T : Any>(private val group: Group<T>) : Counter<T> {
     private val innerValue = atomic(group.zero)
 
     override fun add(delta: T) {

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

@@ -74,7 +74,7 @@ public class DoubleHistogramSpace(
     }
 
     override fun produce(builder: HistogramBuilder<Double>.() -> Unit): IndexedHistogram<Double, Double> {
-        val ndCounter = StructureND.auto(shape) { Counter.real() }
+        val ndCounter = StructureND.auto(shape) { Counter.double() }
         val hBuilder = HistogramBuilder<Double> { point, value ->
             val index = getIndex(point)
             ndCounter[index].add(value.toDouble())

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

@@ -41,7 +41,6 @@ public class IndexedHistogram<T : Comparable<T>, V : Any>(
         get() = DefaultStrides(context.shape).asSequence().map {
             context.produceBin(it, values[it])
         }.asIterable()
-
 }
 
 /**

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

@@ -39,7 +39,7 @@ public class TreeHistogram(
 @PublishedApi
 internal class TreeHistogramBuilder(val binFactory: (Double) -> UnivariateDomain) : UnivariateHistogramBuilder {
 
-    internal class BinCounter(val domain: UnivariateDomain, val counter: Counter<Double> = Counter.real()) :
+    internal class BinCounter(val domain: UnivariateDomain, val counter: Counter<Double> = Counter.double()) :
         ClosedFloatingPointRange<Double> by domain.range
 
     private val bins: TreeMap<Double, BinCounter> = TreeMap()

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

@@ -42,7 +42,7 @@ public interface UnivariateHistogram : Histogram<Double, UnivariateBin> {
         /**
          * Build and fill a [UnivariateHistogram]. Returns a read-only histogram.
          */
-        public fun uniform(
+        public inline fun uniform(
             binSize: Double,
             start: Double = 0.0,
             builder: UnivariateHistogramBuilder.() -> Unit,
@@ -51,7 +51,7 @@ public interface UnivariateHistogram : Histogram<Double, UnivariateBin> {
         /**
          * Build and fill a histogram with custom borders. Returns a read-only histogram.
          */
-        public fun custom(
+        public inline fun custom(
             borders: DoubleArray,
             builder: UnivariateHistogramBuilder.() -> Unit,
         ): UnivariateHistogram = TreeHistogramSpace.custom(borders).fill(builder)

kmath-tensorflow/build.gradle.kts

@@ -0,0 +1,15 @@
+plugins {
+    id("ru.mipt.npm.gradle.jvm")
+}
+
+description = "Google tensorflow connector"
+
+dependencies {
+    api(project(":kmath-tensors"))
+    api("org.tensorflow:tensorflow-core-api:0.3.3")
+    testImplementation("org.tensorflow:tensorflow-core-platform:0.3.3")
+}
+
+readme {
+    maturity = ru.mipt.npm.gradle.Maturity.PROTOTYPE
+}

kmath-tensorflow/src/main/kotlin/space/kscience/kmath/tensorflow/DoubleTensorFlowAlgebra.kt

@@ -0,0 +1,75 @@
+package space.kscience.kmath.tensorflow
+
+import org.tensorflow.Graph
+import org.tensorflow.Output
+import org.tensorflow.ndarray.NdArray
+import org.tensorflow.op.core.Constant
+import org.tensorflow.types.TFloat64
+import space.kscience.kmath.expressions.Symbol
+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.DoubleField
+
+public class DoubleTensorFlowOutput(
+    graph: Graph,
+    output: Output<TFloat64>,
+) : TensorFlowOutput<Double, TFloat64>(graph, output) {
+
+    override fun org.tensorflow.Tensor.actualizeTensor(): NdArray<Double> = this as TFloat64
+
+}
+
+public class DoubleTensorFlowAlgebra internal constructor(
+    graph: Graph,
+) : TensorFlowAlgebra<Double, TFloat64, DoubleField>(graph) {
+
+    override val elementAlgebra: DoubleField get() = DoubleField
+
+    override fun structureND(
+        shape: Shape,
+        initializer: DoubleField.(IntArray) -> Double,
+    ): StructureND<Double> {
+        val res = TFloat64.tensorOf(org.tensorflow.ndarray.Shape.of(*shape.toLongArray())) { array ->
+            DefaultStrides(shape).forEach { index ->
+                array.setDouble(elementAlgebra.initializer(index), *index.toLongArray())
+            }
+        }
+        return DoubleTensorFlowOutput(graph, ops.constant(res).asOutput())
+    }
+
+    override fun StructureND<Double>.asTensorFlow(): TensorFlowOutput<Double, TFloat64> =
+        if (this is TensorFlowOutput<Double, *> && output.type() == TFloat64::class.java) {
+            @Suppress("UNCHECKED_CAST")
+            this as TensorFlowOutput<Double, TFloat64>
+        } else {
+            val res = TFloat64.tensorOf(org.tensorflow.ndarray.Shape.of(*shape.toLongArray())) { array ->
+                @OptIn(PerformancePitfall::class)
+                elements().forEach { (index, value) ->
+                    array.setDouble(value, *index.toLongArray())
+                }
+            }
+            DoubleTensorFlowOutput(graph, ops.constant(res).asOutput())
+        }
+
+    override fun Output<TFloat64>.wrap(): TensorFlowOutput<Double, TFloat64> = DoubleTensorFlowOutput(graph, this)
+
+    override fun const(value: Double): Constant<TFloat64> = ops.constant(value)
+
+
+}
+
+public fun DoubleField.produceWithTF(
+    block: DoubleTensorFlowAlgebra.() -> StructureND<Double>,
+): StructureND<Double> = Graph().use { graph ->
+    val scope = DoubleTensorFlowAlgebra(graph)
+    scope.export(scope.block())
+}
+
+public fun DoubleField.produceMapWithTF(
+    block: DoubleTensorFlowAlgebra.() -> Map<Symbol, StructureND<Double>>,
+): Map<Symbol, StructureND<Double>> = Graph().use { graph ->
+    val scope = DoubleTensorFlowAlgebra(graph)
+    scope.block().mapValues { scope.export(it.value) }
+}

kmath-tensorflow/src/main/kotlin/space/kscience/kmath/tensorflow/IntTensorFlowAlgebra.kt

@@ -0,0 +1,21 @@
+package space.kscience.kmath.tensorflow
+
+import org.tensorflow.Graph
+import org.tensorflow.Output
+import org.tensorflow.ndarray.NdArray
+import org.tensorflow.types.TInt32
+import org.tensorflow.types.TInt64
+
+public class IntTensorFlowOutput(
+    graph: Graph,
+    output: Output<TInt32>,
+) : TensorFlowOutput<Int, TInt32>(graph, output) {
+    override fun org.tensorflow.Tensor.actualizeTensor(): NdArray<Int> = this as TInt32
+}
+
+public class LongTensorFlowOutput(
+    graph: Graph,
+    output: Output<TInt64>,
+) : TensorFlowOutput<Long, TInt64>(graph, output) {
+    override fun org.tensorflow.Tensor.actualizeTensor(): NdArray<Long> = this as TInt64
+}

kmath-tensorflow/src/main/kotlin/space/kscience/kmath/tensorflow/TensorFlowAlgebra.kt

@@ -0,0 +1,237 @@
+package space.kscience.kmath.tensorflow
+
+
+import org.tensorflow.Graph
+import org.tensorflow.Operand
+import org.tensorflow.Output
+import org.tensorflow.Session
+import org.tensorflow.ndarray.NdArray
+import org.tensorflow.op.Ops
+import org.tensorflow.op.core.Constant
+import org.tensorflow.op.core.Max
+import org.tensorflow.op.core.Min
+import org.tensorflow.op.core.Sum
+import org.tensorflow.types.TInt32
+import org.tensorflow.types.family.TType
+import space.kscience.kmath.misc.PerformancePitfall
+import space.kscience.kmath.misc.UnstableKMathAPI
+import space.kscience.kmath.nd.Shape
+import space.kscience.kmath.nd.StructureND
+import space.kscience.kmath.operations.Ring
+import space.kscience.kmath.tensors.api.Tensor
+import space.kscience.kmath.tensors.api.TensorAlgebra
+
+internal fun IntArray.toLongArray() = LongArray(size) { get(it).toLong() }
+internal fun LongArray.toIntArray() = IntArray(size) { get(it).toInt() }
+
+internal val <T> NdArray<T>.scalar: T get() = getObject()
+
+
+public sealed interface TensorFlowTensor<T> : Tensor<T>
+
+@JvmInline
+public value class TensorFlowArray<T>(public val tensor: NdArray<T>) : Tensor<T> {
+    override val shape: Shape get() = tensor.shape().asArray().toIntArray()
+
+    override fun get(index: IntArray): T = tensor.getObject(*index.toLongArray())
+
+    //TODO implement native element sequence
+
+    override fun set(index: IntArray, value: T) {
+        tensor.setObject(value, *index.toLongArray())
+    }
+}
+
+public abstract class TensorFlowOutput<T, TT : TType>(
+    protected val graph: Graph,
+    output: Output<TT>,
+) : TensorFlowTensor<T> {
+
+    public var output: Output<TT> = output
+        internal set
+
+    override val shape: Shape get() = output.shape().asArray().toIntArray()
+
+    protected abstract fun org.tensorflow.Tensor.actualizeTensor(): NdArray<T>
+
+    internal val actualTensor by lazy {
+        Session(graph).use { session ->
+            TensorFlowArray(session.runner().fetch(output).run().first().actualizeTensor())
+        }
+    }
+
+    override fun get(index: IntArray): T = actualTensor[index]
+
+    @PerformancePitfall
+    override fun elements(): Sequence<Pair<IntArray, T>> = actualTensor.elements()
+
+    override fun set(index: IntArray, value: T) {
+        actualTensor[index] = value
+    }
+
+}
+
+
+public abstract class TensorFlowAlgebra<T, TT : TType, A : Ring<T>> internal constructor(
+    protected val graph: Graph,
+) : TensorAlgebra<T, A> {
+
+    protected val ops: Ops by lazy { Ops.create(graph) }
+
+    protected abstract fun StructureND<T>.asTensorFlow(): TensorFlowOutput<T, TT>
+
+    protected abstract fun Output<TT>.wrap(): TensorFlowOutput<T, TT>
+
+    protected abstract fun const(value: T): Constant<TT>
+
+    override fun StructureND<T>.valueOrNull(): T? = if (shape contentEquals intArrayOf(1))
+        get(Shape(0)) else null
+
+    private inline fun StructureND<T>.biOp(
+        other: StructureND<T>,
+        operation: (left: Operand<TT>, right: Operand<TT>) -> Operand<TT>,
+    ): TensorFlowOutput<T, TT> {
+        val left = asTensorFlow().output
+        val right = other.asTensorFlow().output
+        return operation(left, right).asOutput().wrap()
+    }
+
+    private inline fun T.biOp(
+        other: StructureND<T>,
+        operation: (left: Operand<TT>, right: Operand<TT>) -> Operand<TT>,
+    ): TensorFlowOutput<T, TT> {
+        val left = const(this)
+        val right = other.asTensorFlow().output
+        return operation(left, right).asOutput().wrap()
+    }
+
+    private inline fun StructureND<T>.biOp(
+        value: T,
+        operation: (left: Operand<TT>, right: Operand<TT>) -> Operand<TT>,
+    ): TensorFlowOutput<T, TT> {
+        val left = asTensorFlow().output
+        val right = const(value)
+        return operation(left, right).asOutput().wrap()
+    }
+
+    private inline fun Tensor<T>.inPlaceOp(
+        other: StructureND<T>,
+        operation: (left: Operand<TT>, right: Operand<TT>) -> Operand<TT>,
+    ): Unit {
+        val origin = asTensorFlow()
+        val left = origin.output
+        val right = other.asTensorFlow().output
+        origin.output = operation(left, right).asOutput()
+    }
+
+    private inline fun Tensor<T>.inPlaceOp(
+        value: T,
+        operation: (left: Operand<TT>, right: Operand<TT>) -> Operand<TT>,
+    ): Unit {
+        val origin = asTensorFlow()
+        val left = origin.output
+        val right = const(value)
+        origin.output = operation(left, right).asOutput()
+    }
+
+    private inline fun StructureND<T>.unOp(operation: (Operand<TT>) -> Operand<TT>): TensorFlowOutput<T, TT> =
+        operation(asTensorFlow().output).asOutput().wrap()
+
+    override fun T.plus(arg: StructureND<T>): TensorFlowOutput<T, TT> = biOp(arg, ops.math::add)
+
+    override fun StructureND<T>.plus(arg: T): TensorFlowOutput<T, TT> = biOp(arg, ops.math::add)
+
+    override fun StructureND<T>.plus(arg: StructureND<T>): TensorFlowOutput<T, TT> = biOp(arg, ops.math::add)
+
+    override fun Tensor<T>.plusAssign(value: T): Unit = inPlaceOp(value, ops.math::add)
+
+    override fun Tensor<T>.plusAssign(arg: StructureND<T>): Unit = inPlaceOp(arg, ops.math::add)
+
+    override fun StructureND<T>.minus(arg: T): TensorFlowOutput<T, TT> = biOp(arg, ops.math::sub)
+
+    override fun StructureND<T>.minus(arg: StructureND<T>): TensorFlowOutput<T, TT> = biOp(arg, ops.math::sub)
+
+    override fun T.minus(arg: StructureND<T>): Tensor<T> = biOp(arg, ops.math::sub)
+
+    override fun Tensor<T>.minusAssign(value: T): Unit = inPlaceOp(value, ops.math::sub)
+
+    override fun Tensor<T>.minusAssign(arg: StructureND<T>): Unit = inPlaceOp(arg, ops.math::sub)
+
+    override fun T.times(arg: StructureND<T>): TensorFlowOutput<T, TT> = biOp(arg, ops.math::mul)
+
+    override fun StructureND<T>.times(arg: T): TensorFlowOutput<T, TT> = biOp(arg, ops.math::mul)
+
+    override fun StructureND<T>.times(arg: StructureND<T>): TensorFlowOutput<T, TT> = biOp(arg, ops.math::mul)
+
+    override fun Tensor<T>.timesAssign(value: T): Unit = inPlaceOp(value, ops.math::mul)
+
+    override fun Tensor<T>.timesAssign(arg: StructureND<T>): Unit = inPlaceOp(arg, ops.math::mul)
+
+    override fun StructureND<T>.unaryMinus(): TensorFlowOutput<T, TT> = unOp(ops.math::neg)
+
+    override fun Tensor<T>.get(i: Int): Tensor<T> = unOp {
+        TODO("Not yet implemented")
+    }
+
+    override fun Tensor<T>.transpose(i: Int, j: Int): Tensor<T> = unOp {
+        ops.linalg.transpose(it, ops.constant(intArrayOf(i, j)))
+    }
+
+    override fun Tensor<T>.view(shape: IntArray): Tensor<T> = unOp {
+        ops.reshape(it, ops.constant(shape))
+    }
+
+    override fun Tensor<T>.viewAs(other: StructureND<T>): Tensor<T> = biOp(other) { l, r ->
+        ops.reshape(l, ops.shape(r))
+    }
+
+    override fun StructureND<T>.dot(other: StructureND<T>): TensorFlowOutput<T, TT> = biOp(other) { l, r ->
+        ops.linalg.matMul(
+            if (l.asTensor().shape().numDimensions() == 1) ops.expandDims(l,ops.constant(0)) else l,
+            if (r.asTensor().shape().numDimensions() == 1) ops.expandDims(r,ops.constant(-1)) else r)
+    }
+
+    override fun diagonalEmbedding(
+        diagonalEntries: Tensor<T>,
+        offset: Int,
+        dim1: Int,
+        dim2: Int,
+    ): TensorFlowOutput<T, TT> = diagonalEntries.unOp {
+        TODO()
+    }
+
+    override fun StructureND<T>.sum(): T = unOp {
+        ops.sum(it, ops.constant(intArrayOf()))
+    }.value()
+
+    override fun StructureND<T>.sum(dim: Int, keepDim: Boolean): TensorFlowOutput<T, TT> = unOp {
+        ops.sum(it, ops.constant(dim), Sum.keepDims(keepDim))
+    }
+
+    override fun StructureND<T>.min(): T = unOp {
+        ops.min(it, ops.constant(intArrayOf()))
+    }.value()
+
+    override fun StructureND<T>.min(dim: Int, keepDim: Boolean): Tensor<T> = unOp {
+        ops.min(it, ops.constant(dim), Min.keepDims(keepDim))
+    }
+
+    override fun StructureND<T>.max(): T = unOp {
+        ops.max(it, ops.constant(intArrayOf()))
+    }.value()
+
+    override fun StructureND<T>.max(dim: Int, keepDim: Boolean): Tensor<T> = unOp {
+        ops.max(it, ops.constant(dim), Max.keepDims(keepDim))
+    }
+
+    override fun StructureND<T>.argMax(dim: Int, keepDim: Boolean): Tensor<Int> = IntTensorFlowOutput(
+        graph,
+        ops.math.argMax(asTensorFlow().output, ops.constant(dim), TInt32::class.java).output()
+    ).actualTensor
+
+    @OptIn(UnstableKMathAPI::class)
+    override fun export(arg: StructureND<T>): StructureND<T> =
+        if (arg is TensorFlowOutput<T, *>) arg.actualTensor else arg
+}
+
+//TODO add TensorFlow expressions

kmath-tensorflow/src/test/kotlin/space/kscience/kmath/tensorflow/DoubleTensorFlowOps.kt

@@ -0,0 +1,19 @@
+package space.kscience.kmath.tensorflow
+
+import org.junit.jupiter.api.Test
+import space.kscience.kmath.nd.StructureND
+import space.kscience.kmath.nd.structureND
+import space.kscience.kmath.operations.DoubleField
+
+class DoubleTensorFlowOps {
+    @Test
+    fun basicOps() {
+        val res = DoubleField.produceWithTF {
+            val initial = structureND(2, 2) { 1.0 }
+
+            initial + (initial * 2.0)
+        }
+        println(StructureND.toString(res))
+    }
+
+}

kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/api/TensorAlgebra.kt

@@ -208,7 +208,7 @@ public interface TensorAlgebra<T, A : Ring<T>> : RingOpsND<T, A> {
      *
      * 3. If the first argument is 1-dimensional and the second argument is 2-dimensional,
      * a 1 is prepended to its dimension for the purpose of the matrix multiply.
-     * After the matrix multiply, the prepended dimension is removed.
+     * After the matrix multiply, depending on the implementation the prepended dimension might be removed.
      *
      * 4. If the first argument is 2-dimensional and the second argument is 1-dimensional,
      * the matrix-vector product is returned.

kmath-tensors/src/commonMain/kotlin/space/kscience/kmath/tensors/core/DoubleTensorAlgebra.kt

@@ -424,13 +424,13 @@ public open class DoubleTensorAlgebra :
             dotTo(a.as2D(), b.as2D(), res.as2D(), l, m1, n)
         }
 
-        if (penultimateDim) {
+        return if (penultimateDim) {
-            return resTensor.view(resTensor.shape.dropLast(2).toIntArray() + intArrayOf(resTensor.shape.last()))
+            resTensor.view(resTensor.shape.dropLast(2).toIntArray() + intArrayOf(resTensor.shape.last()))
+        } else if (lastDim) {
+            resTensor.view(resTensor.shape.dropLast(1).toIntArray())
+        } else {
+            resTensor
         }
-        if (lastDim) {
-            return resTensor.view(resTensor.shape.dropLast(1).toIntArray())
-        }
-        return resTensor
     }
 
     override fun diagonalEmbedding(

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

@@ -3,6 +3,8 @@
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
+@file:OptIn(PerformancePitfall::class)
+
 package space.kscience.kmath.viktor
 
 import org.jetbrains.bio.viktor.F64Array

settings.gradle.kts

@@ -29,6 +29,7 @@ include(
     ":kmath-commons",
     ":kmath-viktor",
     ":kmath-multik",
+    ":kmath-tensorflow",
     ":kmath-optimization",
     ":kmath-stat",
     ":kmath-nd4j",