Refactor buffer factories

CHANGELOG.md

@@ -9,7 +9,7 @@
 - Exponential operations merged with hyperbolic functions
 - Space is replaced by Group. Space is reserved for vector spaces.
 - VectorSpace is now a vector space
-- 
+- Buffer factories for primitives moved to MutableBuffer.Companion
 
 ### Deprecated
 

kmath-core/api/kmath-core.api

@@ -432,7 +432,7 @@ public final class space/kscience/kmath/expressions/SymbolIndexerKt {
 	public static final fun withSymbols ([Lspace/kscience/kmath/expressions/Symbol;Lkotlin/jvm/functions/Function1;)Ljava/lang/Object;
 }
 
-public final class space/kscience/kmath/linear/BufferLinearSpace : space/kscience/kmath/linear/LinearSpace {
+public final class space/kscience/kmath/linear/BufferedLinearSpace : space/kscience/kmath/linear/LinearSpace {
 	public fun <init> (Lspace/kscience/kmath/operations/Ring;Lkotlin/jvm/functions/Function2;)V
 	public fun buildMatrix (IILkotlin/jvm/functions/Function3;)Lspace/kscience/kmath/nd/Structure2D;
 	public fun buildVector (ILkotlin/jvm/functions/Function2;)Lspace/kscience/kmath/structures/Buffer;
@@ -2115,7 +2115,6 @@ public abstract interface class space/kscience/kmath/structures/Buffer {
 public final class space/kscience/kmath/structures/Buffer$Companion {
 	public final fun auto (Lkotlin/reflect/KClass;ILkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/structures/Buffer;
 	public final fun boxing (ILkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/structures/Buffer;
-	public final fun real-8hrHhI4 (ILkotlin/jvm/functions/Function1;)[D
 }
 
 public final class space/kscience/kmath/structures/Buffer$DefaultImpls {
@@ -2123,15 +2122,17 @@ public final class space/kscience/kmath/structures/Buffer$DefaultImpls {
 }
 
 public final class space/kscience/kmath/structures/BufferKt {
-	public static final fun ListBuffer (ILkotlin/jvm/functions/Function1;)Ljava/util/List;
 	public static final fun asBuffer (Ljava/util/List;)Ljava/util/List;
 	public static final fun asBuffer ([Ljava/lang/Object;)Lspace/kscience/kmath/structures/ArrayBuffer;
-	public static final fun asIterable (Lspace/kscience/kmath/structures/Buffer;)Ljava/lang/Iterable;
+	public static final fun asMutableBuffer (Ljava/util/List;)Ljava/util/List;
 	public static final fun asReadOnly (Lspace/kscience/kmath/structures/Buffer;)Lspace/kscience/kmath/structures/Buffer;
-	public static final fun asSequence (Lspace/kscience/kmath/structures/Buffer;)Lkotlin/sequences/Sequence;
 	public static final fun getIndices (Lspace/kscience/kmath/structures/Buffer;)Lkotlin/ranges/IntRange;
+}
+
+public final class space/kscience/kmath/structures/BufferOperationKt {
+	public static final fun asIterable (Lspace/kscience/kmath/structures/Buffer;)Ljava/lang/Iterable;
+	public static final fun asSequence (Lspace/kscience/kmath/structures/Buffer;)Lkotlin/sequences/Sequence;
 	public static final fun toList (Lspace/kscience/kmath/structures/Buffer;)Ljava/util/List;
-	public static final fun toMutableList (Lspace/kscience/kmath/structures/Buffer;)Ljava/util/List;
 }
 
 public abstract interface class space/kscience/kmath/structures/FlaggedBuffer : space/kscience/kmath/structures/Buffer {
@@ -2316,7 +2317,11 @@ public abstract interface class space/kscience/kmath/structures/MutableBuffer :
 public final class space/kscience/kmath/structures/MutableBuffer$Companion {
 	public final fun auto (Lkotlin/reflect/KClass;ILkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/structures/MutableBuffer;
 	public final fun boxing (ILkotlin/jvm/functions/Function1;)Lspace/kscience/kmath/structures/MutableBuffer;
+	public final fun float-YxruXGw (ILkotlin/jvm/functions/Function1;)[F
+	public final fun int-Ye6GY2U (ILkotlin/jvm/functions/Function1;)[I
+	public final fun long-BuQOeTY (ILkotlin/jvm/functions/Function1;)[J
 	public final fun real-8hrHhI4 (ILkotlin/jvm/functions/Function1;)[D
+	public final fun short-1yRgbGw (ILkotlin/jvm/functions/Function1;)[S
 }
 
 public final class space/kscience/kmath/structures/MutableBuffer$DefaultImpls {

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

@@ -9,7 +9,7 @@ import space.kscience.kmath.structures.VirtualBuffer
 import space.kscience.kmath.structures.indices
 
 
-public class BufferLinearSpace<T : Any, A : Ring<T>>(
+public class BufferedLinearSpace<T : Any, A : Ring<T>>(
     override val elementAlgebra: A,
     private val bufferFactory: BufferFactory<T>,
 ) : LinearSpace<T, A> {

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

@@ -6,9 +6,20 @@ import space.kscience.kmath.nd.as1D
  * A group of methods to resolve equation A dot X = B, where A and B are matrices or vectors
  */
 public interface LinearSolver<T : Any> {
+    /**
+     * Solve a dot x = b matrix equation and return x
+     */
     public fun solve(a: Matrix<T>, b: Matrix<T>): Matrix<T>
+
+    /**
+     * Solve a dot x = b vector equation and return b
+     */
     public fun solve(a: Matrix<T>, b: Point<T>): Point<T> = solve(a, b.asMatrix()).asVector()
-    public fun inverse(a: Matrix<T>): Matrix<T>
+
+    /**
+     * Get inverse of a matrix
+     */
+    public fun inverse(matrix: Matrix<T>): Matrix<T>
 }
 
 /**

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

@@ -5,6 +5,7 @@ import space.kscience.kmath.nd.*
 import space.kscience.kmath.operations.*
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.BufferFactory
+import space.kscience.kmath.structures.RealBuffer
 import kotlin.reflect.KClass
 
 /**
@@ -174,9 +175,9 @@ public interface LinearSpace<T : Any, out A : Ring<T>> {
         public fun <T : Any, A : Ring<T>> buffered(
             algebra: A,
             bufferFactory: BufferFactory<T> = Buffer.Companion::boxing,
-        ): LinearSpace<T, A> = BufferLinearSpace(algebra,bufferFactory)
+        ): LinearSpace<T, A> = BufferedLinearSpace(algebra,bufferFactory)
 
-        public val real: LinearSpace<Double, RealField> = buffered(RealField, Buffer.Companion::real)
+        public val real: LinearSpace<Double, RealField> = buffered(RealField, ::RealBuffer)
 
         /**
          * Automatic buffered matrix, unboxed if it is possible

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

@@ -3,10 +3,10 @@ package space.kscience.kmath.linear
 import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.nd.getFeature
 import space.kscience.kmath.operations.*
-import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.BufferAccessor2D
 import space.kscience.kmath.structures.MutableBuffer
 import space.kscience.kmath.structures.MutableBufferFactory
+import space.kscience.kmath.structures.RealBuffer
 
 /**
  * Common implementation of [LupDecompositionFeature].
@@ -152,7 +152,7 @@ public inline fun <reified T : Comparable<T>> LinearSpace<T, Field<T>>.lup(
 ): LupDecomposition<T> = lup(MutableBuffer.Companion::auto, matrix, checkSingular)
 
 public fun LinearSpace<Double, RealField>.lup(matrix: Matrix<Double>): LupDecomposition<Double> =
-    lup(Buffer.Companion::real, matrix) { it < 1e-11 }
+    lup(::RealBuffer, matrix) { it < 1e-11 }
 
 public fun <T : Any> LupDecomposition<T>.solveWithLup(
     factory: MutableBufferFactory<T>,
@@ -230,7 +230,7 @@ public inline fun <reified T : Comparable<T>> LinearSpace<T, Field<T>>.inverseWi
 @OptIn(UnstableKMathAPI::class)
 public fun LinearSpace<Double, RealField>.solveWithLup(a: Matrix<Double>, b: Matrix<Double>): Matrix<Double> {
     // Use existing decomposition if it is provided by matrix
-    val bufferFactory: MutableBufferFactory<Double> = MutableBuffer.Companion::real
+    val bufferFactory: MutableBufferFactory<Double> = ::RealBuffer
     val decomposition: LupDecomposition<Double> = a.getFeature() ?: lup(bufferFactory, a) { it < 1e-11 }
     return decomposition.solveWithLup(bufferFactory, b)
 }

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

@@ -48,8 +48,8 @@ public interface NDStructure<T> {
     public override fun hashCode(): Int
 
     /**
-     * Feature is additional property or hint that does not directly affect the structure, but could in some cases help
+     * Feature is some additional strucure information which allows to access it special properties or hints.
-     * optimize operations and performance. If the feature is not present, null is defined.
+     * If the feature is not present, null is returned.
      */
     @UnstableKMathAPI
     public fun <F : Any> getFeature(type: KClass<F>): F? = null

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

@@ -5,7 +5,6 @@ import space.kscience.kmath.operations.ExtendedField
 import space.kscience.kmath.operations.NumbersAddOperations
 import space.kscience.kmath.operations.RealField
 import space.kscience.kmath.operations.ScaleOperations
-import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.RealBuffer
 import kotlin.contracts.InvocationKind
 import kotlin.contracts.contract
@@ -13,7 +12,7 @@ import kotlin.contracts.contract
 @OptIn(UnstableKMathAPI::class)
 public class RealNDField(
     shape: IntArray,
-) : BufferedNDField<Double, RealField>(shape, RealField, Buffer.Companion::real),
+) : BufferedNDField<Double, RealField>(shape, RealField, ::RealBuffer),
     NumbersAddOperations<NDStructure<Double>>,
     ScaleOperations<NDStructure<Double>>,
     ExtendedField<NDStructure<Double>> {

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

@@ -56,3 +56,12 @@ public fun <T> NDStructure<T>.as1D(): Structure1D<T> = this as? Structure1D<T> ?
  * Represent this buffer as 1D structure
  */
 public fun <T> Buffer<T>.asND(): Structure1D<T> = Buffer1DWrapper(this)
+
+/**
+ * Expose inner buffer of this [Structure1D] if possible
+ */
+internal fun <T : Any> Structure1D<T>.unwrap(): Buffer<T> = when {
+    this is Buffer1DWrapper<T> -> buffer
+    this is Structure1DWrapper && structure is NDBuffer<T> -> structure.buffer
+    else -> this
+}

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

@@ -86,4 +86,9 @@ public fun <T> NDStructure<T>.as2D(): Structure2D<T> = this as? Structure2D<T> ?
     else -> error("Can't create 2d-structure from ${shape.size}d-structure")
 }
 
-internal fun <T> Structure2D<T>.unwrap(): NDStructure<T> = if (this is Structure2DWrapper) structure else this
+/**
+ * Expose inner [NDStructure] if possible
+ */
+internal fun <T> Structure2D<T>.unwrap(): NDStructure<T> =
+    if (this is Structure2DWrapper) structure
+    else this

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

@@ -44,21 +44,12 @@ public interface Buffer<out T> {
         asSequence().mapIndexed { index, value -> value == other[index] }.all { it }
 
     public companion object {
-        /**
-         * Creates a [RealBuffer] with the specified [size], where each element is calculated by calling the specified
-         * [initializer] function.
-         */
-        public inline fun real(size: Int, initializer: (Int) -> Double): RealBuffer =
-            RealBuffer(size) { initializer(it) }
-
         /**
          * Creates a [ListBuffer] of given type [T] with given [size]. Each element is calculated by calling the
          * specified [initializer] function.
          */
         public inline fun <T> boxing(size: Int, initializer: (Int) -> T): Buffer<T> =
-            ListBuffer(List(size, initializer))
+            List(size, initializer).asBuffer()
-
-        // TODO add resolution based on Annotation or companion resolution
 
         /**
          * Creates a [Buffer] of given [type]. If the type is primitive, specialized buffers are used ([IntBuffer],
@@ -69,11 +60,11 @@ public interface Buffer<out T> {
         @Suppress("UNCHECKED_CAST")
         public inline fun <T : Any> auto(type: KClass<T>, size: Int, initializer: (Int) -> T): Buffer<T> =
             when (type) {
-                Double::class -> RealBuffer(size) { initializer(it) as Double } as Buffer<T>
+                Double::class -> MutableBuffer.real(size) { initializer(it) as Double } as Buffer<T>
-                Short::class -> ShortBuffer(size) { initializer(it) as Short } as Buffer<T>
+                Short::class -> MutableBuffer.short(size) { initializer(it) as Short } as Buffer<T>
-                Int::class -> IntBuffer(size) { initializer(it) as Int } as Buffer<T>
+                Int::class -> MutableBuffer.int(size) { initializer(it) as Int } as Buffer<T>
-                Long::class -> LongBuffer(size) { initializer(it) as Long } as Buffer<T>
+                Long::class -> MutableBuffer.long(size) { initializer(it) as Long } as Buffer<T>
-                Float::class -> FloatBuffer(size) { initializer(it) as Float } as Buffer<T>
+                Float::class -> MutableBuffer.float(size) { initializer(it) as Float } as Buffer<T>
                 else -> boxing(size, initializer)
             }
 
@@ -89,41 +80,6 @@ public interface Buffer<out T> {
     }
 }
 
-/**
- * Creates a sequence that returns all elements from this [Buffer].
- */
-public fun <T> Buffer<T>.asSequence(): Sequence<T> = Sequence(::iterator)
-
-/**
- * Creates an iterable that returns all elements from this [Buffer].
- */
-public fun <T> Buffer<T>.asIterable(): Iterable<T> = Iterable(::iterator)
-
-/**
- * Returns a new [List] containing all elements of this buffer.
- */
-public fun <T> Buffer<T>.toList(): List<T> = when (this) {
-    is ArrayBuffer<T> -> array.toList()
-    is ListBuffer<T> -> list.toList()
-    is MutableListBuffer<T> -> list.toList()
-    else -> asSequence().toList()
-}
-
-/**
- * Returns a new [MutableList] filled with all elements of this buffer.
- */
-public fun <T> Buffer<T>.toMutableList(): MutableList<T> = when (this) {
-    is ArrayBuffer<T> -> array.toMutableList()
-    is ListBuffer<T> -> list.toMutableList()
-    is MutableListBuffer<T> -> list.toMutableList()
-    else -> asSequence().toMutableList()
-}
-
-/**
- * Returns a new [Array] containing all elements of this buffer.
- */
-public inline fun <reified T> Buffer<T>.toTypedArray(): Array<T> = asSequence().toList().toTypedArray()
-
 /**
  * Returns an [IntRange] of the valid indices for this [Buffer].
  */
@@ -146,6 +102,44 @@ public interface MutableBuffer<T> : Buffer<T> {
     public fun copy(): MutableBuffer<T>
 
     public companion object {
+
+        /**
+         * Creates a [RealBuffer] with the specified [size], where each element is calculated by calling the specified
+         * [initializer] function.
+         */
+        public inline fun real(size: Int, initializer: (Int) -> Double): RealBuffer =
+            RealBuffer(size, initializer)
+
+        /**
+         * Creates a [ShortBuffer] with the specified [size], where each element is calculated by calling the specified
+         * [initializer] function.
+         */
+        public inline fun short(size: Int, initializer: (Int) -> Short): ShortBuffer =
+            ShortBuffer(size, initializer)
+
+        /**
+         * Creates a [IntBuffer] with the specified [size], where each element is calculated by calling the specified
+         * [initializer] function.
+         */
+        public inline fun int(size: Int, initializer: (Int) -> Int): IntBuffer =
+            IntBuffer(size, initializer)
+
+        /**
+         * Creates a [LongBuffer] with the specified [size], where each element is calculated by calling the specified
+         * [initializer] function.
+         */
+        public inline fun long(size: Int, initializer: (Int) -> Long): LongBuffer =
+            LongBuffer(size, initializer)
+
+
+        /**
+         * Creates a [FloatBuffer] with the specified [size], where each element is calculated by calling the specified
+         * [initializer] function.
+         */
+        public inline fun float(size: Int, initializer: (Int) -> Float): FloatBuffer =
+            FloatBuffer(size, initializer)
+
+
         /**
          * Create a boxing mutable buffer of given type
          */
@@ -161,11 +155,11 @@ public interface MutableBuffer<T> : Buffer<T> {
         @Suppress("UNCHECKED_CAST")
         public inline fun <T : Any> auto(type: KClass<out T>, size: Int, initializer: (Int) -> T): MutableBuffer<T> =
             when (type) {
-                Double::class -> RealBuffer(size) { initializer(it) as Double } as MutableBuffer<T>
+                Double::class -> real(size) { initializer(it) as Double } as MutableBuffer<T>
-                Short::class -> ShortBuffer(size) { initializer(it) as Short } as MutableBuffer<T>
+                Short::class -> short(size) { initializer(it) as Short } as MutableBuffer<T>
-                Int::class -> IntBuffer(size) { initializer(it) as Int } as MutableBuffer<T>
+                Int::class -> int(size) { initializer(it) as Int } as MutableBuffer<T>
-                Float::class -> FloatBuffer(size) { initializer(it) as Float } as MutableBuffer<T>
+                Float::class -> float(size) { initializer(it) as Float } as MutableBuffer<T>
-                Long::class -> LongBuffer(size) { initializer(it) as Long } as MutableBuffer<T>
+                Long::class -> long(size) { initializer(it) as Long } as MutableBuffer<T>
                 else -> boxing(size, initializer)
             }
 
@@ -178,13 +172,6 @@ public interface MutableBuffer<T> : Buffer<T> {
         @Suppress("UNCHECKED_CAST")
         public inline fun <reified T : Any> auto(size: Int, initializer: (Int) -> T): MutableBuffer<T> =
             auto(T::class, size, initializer)
-
-        /**
-         * Creates a [RealBuffer] with the specified [size], where each element is calculated by calling the specified
-         * [initializer] function.
-         */
-        public inline fun real(size: Int, initializer: (Int) -> Double): RealBuffer =
-            RealBuffer(size) { initializer(it) }
     }
 }
 
@@ -207,15 +194,6 @@ public inline class ListBuffer<T>(public val list: List<T>) : Buffer<T> {
  */
 public fun <T> List<T>.asBuffer(): ListBuffer<T> = ListBuffer(this)
 
-/**
- * Creates a new [ListBuffer] with the specified [size], where each element is calculated by calling the specified
- * [init] function.
- *
- * The function [init] is called for each array element sequentially starting from the first one.
- * It should return the value for an array element given its index.
- */
-public inline fun <T> ListBuffer(size: Int, init: (Int) -> T): ListBuffer<T> = List(size, init).asBuffer()
-
 /**
  * [MutableBuffer] implementation over [MutableList].
  *
@@ -236,6 +214,11 @@ public inline class MutableListBuffer<T>(public val list: MutableList<T>) : Muta
     override fun copy(): MutableBuffer<T> = MutableListBuffer(ArrayList(list))
 }
 
+/**
+ * Returns an [ListBuffer] that wraps the original list.
+ */
+public fun <T> MutableList<T>.asMutableBuffer(): MutableListBuffer<T> = MutableListBuffer(this)
+
 /**
  * [MutableBuffer] implementation over [Array].
  *
@@ -244,8 +227,7 @@ public inline class MutableListBuffer<T>(public val list: MutableList<T>) : Muta
  */
 public class ArrayBuffer<T>(internal val array: Array<T>) : MutableBuffer<T> {
     // Can't inline because array is invariant
-    override val size: Int
+    override val size: Int get() = array.size
-        get() = array.size
 
     override operator fun get(index: Int): T = array[index]
 
@@ -263,16 +245,6 @@ public class ArrayBuffer<T>(internal val array: Array<T>) : MutableBuffer<T> {
  */
 public fun <T> Array<T>.asBuffer(): ArrayBuffer<T> = ArrayBuffer(this)
 
-/**
- * Creates a new [ArrayBuffer] with the specified [size], where each element is calculated by calling the specified
- * [init] function.
- *
- * The function [init] is called for each array element sequentially starting from the first one.
- * It should return the value for an array element given its index.
- */
-public inline fun <reified T> ArrayBuffer(size: Int, init: (Int) -> T): ArrayBuffer<T> =
-    Array(size) { i -> init(i) }.asBuffer()
-
 /**
  * Immutable wrapper for [MutableBuffer].
  *
@@ -314,13 +286,3 @@ public class VirtualBuffer<T>(override val size: Int, private val generator: (In
  * Convert this buffer to read-only buffer.
  */
 public fun <T> Buffer<T>.asReadOnly(): Buffer<T> = if (this is MutableBuffer) ReadOnlyBuffer(this) else this
-
-/**
- * Typealias for buffer transformations.
- */
-public typealias BufferTransform<T, R> = (Buffer<T>) -> Buffer<R>
-
-/**
- * Typealias for buffer transformations with suspend function.
- */
-public typealias SuspendBufferTransform<T, R> = suspend (Buffer<T>) -> Buffer<R>

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

@@ -1,7 +1,84 @@
 package space.kscience.kmath.structures
 
+import space.kscience.kmath.misc.UnstableKMathAPI
 
+/**
+ * Typealias for buffer transformations.
+ */
+public typealias BufferTransform<T, R> = (Buffer<T>) -> Buffer<R>
+
+/**
+ * Typealias for buffer transformations with suspend function.
+ */
+public typealias SuspendBufferTransform<T, R> = suspend (Buffer<T>) -> Buffer<R>
+
+
+/**
+ * Creates a sequence that returns all elements from this [Buffer].
+ */
+public fun <T> Buffer<T>.asSequence(): Sequence<T> = Sequence(::iterator)
+
+/**
+ * Creates an iterable that returns all elements from this [Buffer].
+ */
+public fun <T> Buffer<T>.asIterable(): Iterable<T> = Iterable(::iterator)
+
+/**
+ * Returns a new [List] containing all elements of this buffer.
+ */
+public fun <T> Buffer<T>.toList(): List<T> = when (this) {
+    is ArrayBuffer<T> -> array.toList()
+    is ListBuffer<T> -> list.toList()
+    is MutableListBuffer<T> -> list.toList()
+    else -> asSequence().toList()
+}
+
+/**
+ * Returns a new [MutableList] filled with all elements of this buffer.
+ * **NOTE:** this method uses a protective copy, so it should not be used in performance-critical code.
+ */
+@UnstableKMathAPI
+public fun <T> Buffer<T>.toMutableList(): MutableList<T> = when (this) {
+    is ArrayBuffer<T> -> array.toMutableList()
+    is ListBuffer<T> -> list.toMutableList()
+    is MutableListBuffer<T> -> list.toMutableList()
+    else -> MutableList(size, ::get)
+}
+
+/**
+ * Returns a new [Array] containing all elements of this buffer.
+ * **NOTE:** this method uses a protective copy, so it should not be used in performance-critical code.
+ */
+@UnstableKMathAPI
+public inline fun <reified T> Buffer<T>.toTypedArray(): Array<T> = Array(size, ::get)
+
+/**
+ * Create a new buffer from this one with the given mapping function.
+ * Provided [BufferFactory] is used to construct the new buffer.
+ */
 public inline fun <T : Any, reified R : Any> Buffer<T>.map(
     bufferFactory: BufferFactory<R> = Buffer.Companion::auto,
     crossinline block: (T) -> R,
 ): Buffer<R> = bufferFactory(size) { block(get(it)) }
+
+/**
+ * Create a new buffer from this one with the given indexed mapping function.
+ * Provided [BufferFactory] is used to construct the new buffer.
+ */
+public inline fun <T : Any, reified R : Any> Buffer<T>.mapIndexed(
+    bufferFactory: BufferFactory<R> = Buffer.Companion::auto,
+    crossinline block: (index: Int, value: T) -> R,
+): Buffer<R> = bufferFactory(size) { block(it, get(it)) }
+
+/**
+ * Zip two buffers using given [transform].
+ */
+@UnstableKMathAPI
+public inline fun <T1 : Any, T2 : Any, reified R : Any> Buffer<T1>.zip(
+    other: Buffer<T2>,
+    bufferFactory: BufferFactory<R> = Buffer.Companion::auto,
+    crossinline transform: (T1, T2) -> R,
+): Buffer<R> {
+    require(size == other.size) { "Buffer size mismatch in zip: expected $size but found ${other.size}" }
+    return bufferFactory(size) { transform(get(it), other[it]) }
+}

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

@@ -1,8 +1,10 @@
 package space.kscience.kmath.real
 
 import space.kscience.kmath.linear.Point
+import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.operations.Norm
 import space.kscience.kmath.structures.Buffer
+import space.kscience.kmath.structures.MutableBuffer.Companion.real
 import space.kscience.kmath.structures.asBuffer
 import space.kscience.kmath.structures.asIterable
 import space.kscience.kmath.structures.indices
@@ -20,15 +22,16 @@ public operator fun Buffer.Companion.invoke(vararg doubles: Double): RealVector
 /**
  * Fill the vector of given [size] with given [value]
  */
+@UnstableKMathAPI
 public fun Buffer.Companion.same(size: Int, value: Number): RealVector = real(size) { value.toDouble() }
 
 // Transformation methods
 
 public inline fun RealVector.map(transform: (Double) -> Double): RealVector =
-    Buffer.real(size) { transform(get(it)) }
+    real(size) { transform(get(it)) }
 
 public inline fun RealVector.mapIndexed(transform: (index: Int, value: Double) -> Double): RealVector =
-    Buffer.real(size) { transform(it, get(it)) }
+    real(size) { transform(it, get(it)) }
 
 public operator fun RealVector.plus(other: RealVector): RealVector {
     require(size == other.size) { "Vector size $size expected but ${other.size} found" }

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

@@ -4,30 +4,30 @@ import space.kscience.kmath.linear.LinearSpace
 import space.kscience.kmath.linear.asMatrix
 import space.kscience.kmath.linear.transpose
 import space.kscience.kmath.real.plus
-import space.kscience.kmath.structures.Buffer
+import space.kscience.kmath.structures.RealBuffer
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
 internal class RealVectorTest {
     @Test
     fun testSum() {
-        val vector1 = Buffer.real(5) { it.toDouble() }
+        val vector1 = RealBuffer(5) { it.toDouble() }
-        val vector2 =  Buffer.real(5) { 5 - it.toDouble() }
+        val vector2 = RealBuffer(5) { 5 - it.toDouble() }
         val sum = vector1 + vector2
         assertEquals(5.0, sum[2])
     }
 
     @Test
     fun testVectorToMatrix() {
-        val vector =  Buffer.real(5) { it.toDouble() }
+        val vector = RealBuffer(5) { it.toDouble() }
         val matrix = vector.asMatrix()
         assertEquals(4.0, matrix[4, 0])
     }
 
     @Test
     fun testDot() {
-        val vector1 =  Buffer.real(5) { it.toDouble() }
+        val vector1 = RealBuffer(5) { it.toDouble() }
-        val vector2 =  Buffer.real(5) { 5 - it.toDouble() }
+        val vector2 = RealBuffer(5) { 5 - it.toDouble() }
         val matrix1 = vector1.asMatrix()
         val matrix2 = vector2.asMatrix().transpose()
         val product = LinearSpace.real.run { matrix1 dot matrix2 }

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

@@ -2,8 +2,8 @@ package space.kscience.kmath.histogram
 
 import space.kscience.kmath.domains.Domain
 import space.kscience.kmath.linear.Point
-import space.kscience.kmath.structures.ArrayBuffer
 import space.kscience.kmath.structures.RealBuffer
+import space.kscience.kmath.structures.asBuffer
 
 /**
  * The binned data element. Could be a histogram bin with a number of counts or an artificial construct
@@ -40,7 +40,7 @@ public fun interface HistogramBuilder<T : Any>  {
 
 public fun <T : Any, B : Bin<T>> HistogramBuilder<T>.put(point: Point<out T>): Unit = putValue(point, 1.0)
 
-public fun <T : Any> HistogramBuilder<T>.put(vararg point: T): Unit = put(ArrayBuffer(point))
+public fun <T : Any> HistogramBuilder<T>.put(vararg point: T): Unit = put(point.asBuffer())
 
 public fun HistogramBuilder<Double>.put(vararg point: Number): Unit =
     put(RealBuffer(point.map { it.toDouble() }.toDoubleArray()))

kmath-stat/src/commonMain/kotlin/space/kscience/kmath/stat/Distribution.kt

@@ -4,6 +4,7 @@ import space.kscience.kmath.chains.Chain
 import space.kscience.kmath.chains.collect
 import space.kscience.kmath.structures.Buffer
 import space.kscience.kmath.structures.BufferFactory
+import space.kscience.kmath.structures.RealBuffer
 
 public interface Sampler<T : Any> {
     public fun sample(generator: RandomGenerator): Chain<T>
@@ -74,4 +75,4 @@ public fun <T : Any> Sampler<T>.sampleBuffer(
  * Generate a bunch of samples from real distributions
  */
 public fun Sampler<Double>.sampleBuffer(generator: RandomGenerator, size: Int): Chain<Buffer<Double>> =
-    sampleBuffer(generator, size, Buffer.Companion::real)
+    sampleBuffer(generator, size, ::RealBuffer)