DoubleBuffer generator was moved to DoubleBuffer file and factory functions were added for LongArray

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

@@ -6,6 +6,7 @@
 package space.kscience.kmath.structures
 
 import kotlin.jvm.JvmInline
+import kotlin.random.Random.Default.nextDouble
 
 /**
  * Specialized [MutableBuffer] implementation over [DoubleArray].
@@ -42,6 +43,11 @@ public value class DoubleBuffer(public val array: DoubleArray) : MutableBuffer<D
  */
 public inline fun DoubleBuffer(size: Int, init: (Int) -> Double): DoubleBuffer = DoubleBuffer(DoubleArray(size) { init(it) })
 
+/**
+ * A chunk of doubles of given [size].
+ */
+public fun nextDoubleBuffer(size: Int): DoubleBuffer = DoubleBuffer(size) { nextDouble() }
+
 /**
  * Returns a new [DoubleBuffer] of given elements.
  */

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

@@ -12,6 +12,7 @@ import space.kscience.kmath.misc.UnstableKMathAPI
 import space.kscience.kmath.operations.DoubleField
 import space.kscience.kmath.stat.RandomGenerator
 import space.kscience.kmath.stat.nextBuffer
+import space.kscience.kmath.structures.nextDoubleBuffer
 import kotlin.native.concurrent.ThreadLocal
 import kotlin.test.Test
 import kotlin.test.assertEquals
@@ -35,7 +36,7 @@ internal class UniformHistogram1DTest {
 
     @Test
     fun rebinDown() = runTest {
-        val h1 = Histogram.uniform1D(DoubleField, 0.01).produce(generator.nextDoubleBuffer(10000))
+        val h1 = Histogram.uniform1D(DoubleField, 0.01).produce(nextDoubleBuffer(10000))
         val h2 = Histogram.uniform1D(DoubleField,0.03).produceFrom(h1)
 
         assertEquals(10000, h2.bins.sumOf { it.binValue }.toInt())
@@ -43,7 +44,7 @@ internal class UniformHistogram1DTest {
 
     @Test
     fun rebinUp() = runTest {
-        val h1 = Histogram.uniform1D(DoubleField, 0.03).produce(generator.nextDoubleBuffer(10000))
+        val h1 = Histogram.uniform1D(DoubleField, 0.03).produce(nextDoubleBuffer(10000))
         val h2 = Histogram.uniform1D(DoubleField,0.01).produceFrom(h1)
 
         assertEquals(10000, h2.bins.sumOf { it.binValue }.toInt())

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

@@ -8,3 +8,13 @@ package space.kscience.kmath.nd4j
 import space.kscience.kmath.misc.toIntExact
 
 internal fun LongArray.toIntArray(): IntArray = IntArray(size) { this[it].toIntExact() }
+
+internal fun LongArray.linspace(start: Long, stop: Long) = Array(this.size) {
+    start + it * ((stop - start) / (this.size - 1))
+}
+
+internal fun LongArray.zeros() = Array(this.size) { 0 }
+
+internal fun LongArray.ones() = Array(this.size) { 1 }
+
+internal fun repeat(number: Long, size: Int) = LongArray(size) { number }

kmath-stat/src/commonMain/kotlin/space/kscience/kmath/samplers/BoxMullerSampler.kt

@@ -8,6 +8,7 @@ package space.kscience.kmath.samplers
 import space.kscience.kmath.chains.BlockingDoubleChain
 import space.kscience.kmath.stat.RandomGenerator
 import space.kscience.kmath.structures.DoubleBuffer
+import space.kscience.kmath.structures.nextDoubleBuffer
 import kotlin.math.*
 
 /**
@@ -23,8 +24,8 @@ public object BoxMullerSampler : NormalizedGaussianSampler {
         var state = Double.NaN
 
         override fun nextBufferBlocking(size: Int): DoubleBuffer {
-            val xs = generator.nextDoubleBuffer(size)
+            val xs = nextDoubleBuffer(size)
-            val ys = generator.nextDoubleBuffer(size)
+            val ys = nextDoubleBuffer(size)
 
             return DoubleBuffer(size) { index ->
                 if (state.isNaN()) {

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

@@ -8,6 +8,7 @@ package space.kscience.kmath.stat
 import space.kscience.kmath.chains.BlockingDoubleChain
 import space.kscience.kmath.chains.Chain
 import space.kscience.kmath.structures.DoubleBuffer
+import space.kscience.kmath.structures.nextDoubleBuffer
 
 /**
  * A possibly stateful chain producing random values.
@@ -31,7 +32,7 @@ public fun <R> RandomGenerator.chain(generator: suspend RandomGenerator.() -> R)
  * A type-specific double chunk random chain
  */
 public class UniformDoubleChain(public val generator: RandomGenerator) : BlockingDoubleChain {
-    override fun nextBufferBlocking(size: Int): DoubleBuffer = generator.nextDoubleBuffer(size)
+    override fun nextBufferBlocking(size: Int): DoubleBuffer = nextDoubleBuffer(size)
     override suspend fun nextBuffer(size: Int): DoubleBuffer = nextBufferBlocking(size)
 
     override suspend fun fork(): UniformDoubleChain = UniformDoubleChain(generator.fork())

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

@@ -22,11 +22,6 @@ public interface RandomGenerator {
      */
     public fun nextDouble(): Double
 
-    /**
-     * A chunk of doubles of given [size].
-     */
-    public fun nextDoubleBuffer(size: Int): DoubleBuffer = DoubleBuffer(size) { nextDouble() }
-
     /**
      * Gets the next random `Int` from the random number generator.
      *