Added limited polimorphism to Histogram

kmath-core/src/commonMain/kotlin/scientifik/kmath/histogram/FastHistogram.kt

@@ -2,6 +2,7 @@ package scientifik.kmath.histogram
 
 import scientifik.kmath.linear.RealVector
 import scientifik.kmath.linear.toVector
+import scientifik.kmath.structures.Buffer
 import scientifik.kmath.structures.NDStructure
 import scientifik.kmath.structures.ndStructure
 import kotlin.math.floor
@@ -11,7 +12,7 @@ class MultivariateBin(override val center: RealVector, val sizes: RealVector, va
         if (center.size != sizes.size) error("Dimension mismatch in bin creation. Expected ${center.size}, but found ${sizes.size}")
     }
 
-    override fun contains(vector: RealVector): Boolean {
+    override fun contains(vector: Buffer<out Double>): Boolean {
         if (vector.size != center.size) error("Dimension mismatch for input vector. Expected ${center.size}, but found ${vector.size}")
         return vector.asSequence().mapIndexed { i, value -> value in (center[i] - sizes[i] / 2)..(center[i] + sizes[i] / 2) }.all { it }
     }
@@ -70,12 +71,12 @@ class FastHistogram(
     }
 
 
-    override fun get(point: RealVector): MultivariateBin? {
+    override fun get(point: Buffer<out Double>): MultivariateBin? {
         val index = IntArray(dimension) { getIndex(it, point[it]) }
         return bins[index]
     }
 
-    override fun put(point: RealVector) {
+    override fun put(point: Buffer<out Double>) {
         this[point]?.inc() ?: error("Could not find appropriate bin (should not be possible)")
     }
 

kmath-core/src/commonMain/kotlin/scientifik/kmath/histogram/Histogram.kt

@@ -1,15 +1,15 @@
 package scientifik.kmath.histogram
 
-import scientifik.kmath.linear.Vector
-import scientifik.kmath.linear.toVector
 import scientifik.kmath.operations.Space
+import scientifik.kmath.structures.ArrayBuffer
+import scientifik.kmath.structures.Buffer
 
 /**
  * A simple geometric domain
  * TODO move to geometry module
  */
 interface Domain<T: Any> {
-    operator fun contains(vector: Vector<T>): Boolean
+    operator fun contains(vector: Buffer<out T>): Boolean
     val dimension: Int
 }
 
@@ -21,7 +21,7 @@ interface Bin<T: Any> : Domain<T> {
      * The value of this bin
      */
     val value: Number
-    val center: Vector<T>
+    val center: Buffer<T>
 }
 
 interface Histogram<T: Any, out B : Bin<T>> : Iterable<B> {
@@ -29,7 +29,7 @@ interface Histogram<T: Any, out B : Bin<T>> : Iterable<B> {
     /**
      * Find existing bin, corresponding to given coordinates
      */
-    operator fun get(point: Vector<T>): B?
+    operator fun get(point: Buffer<out T>): B?
 
     /**
      * Dimension of the histogram
@@ -39,17 +39,17 @@ interface Histogram<T: Any, out B : Bin<T>> : Iterable<B> {
     /**
      * Increment appropriate bin
      */
-    fun put(point: Vector<T>)
+    fun put(point: Buffer<out T>)
 }
 
-fun Histogram<Double,*>.put(vararg point: Double) = put(point.toVector())
+fun <T: Any> Histogram<T,*>.put(vararg point: T) = put(ArrayBuffer(point))
 
-fun <T: Any> Histogram<T,*>.fill(sequence: Iterable<Vector<T>>) = sequence.forEach { put(it) }
+fun <T: Any> Histogram<T,*>.fill(sequence: Iterable<Buffer<T>>) = sequence.forEach { put(it) }
 
 /**
  * Pass a sequence builder into histogram
  */
-fun <T: Any> Histogram<T, *>.fill(buider: suspend SequenceScope<Vector<T>>.() -> Unit) = fill(sequence(buider).asIterable())
+fun <T: Any> Histogram<T, *>.fill(buider: suspend SequenceScope<Buffer<T>>.() -> Unit) = fill(sequence(buider).asIterable())
 
 /**
  * A space to perform arithmetic operations on histograms

kmath-core/src/commonMain/kotlin/scientifik/kmath/linear/LinearAlgrebra.kt

@@ -4,10 +4,7 @@ import scientifik.kmath.operations.DoubleField
 import scientifik.kmath.operations.Field
 import scientifik.kmath.operations.Space
 import scientifik.kmath.operations.SpaceElement
-import scientifik.kmath.structures.GenericNDField
+import scientifik.kmath.structures.*
-import scientifik.kmath.structures.NDArray
-import scientifik.kmath.structures.NDField
-import scientifik.kmath.structures.get
 
 /**
  * The space for linear elements. Supports scalar product alongside with standard linear operations.
@@ -162,10 +159,8 @@ abstract class VectorSpace<T : Any>(val size: Int, val field: Field<T>) : Space<
 }
 
 
-interface Vector<T : Any> : SpaceElement<Vector<T>, VectorSpace<T>>, Iterable<T> {
+interface Vector<T : Any> : SpaceElement<Vector<T>, VectorSpace<T>>, Buffer<T>, Iterable<T> {
-    val size: Int get() = context.size
+    override val size: Int get() = context.size
-
-    operator fun get(i: Int): T
 
     companion object {
         /**
@@ -261,15 +256,17 @@ class ArrayVector<T : Any> internal constructor(override val context: ArrayVecto
         }
     }
 
-    override fun get(i: Int): T {
+    override fun get(index: Int): T {
-        return array[i]
+        return array[index]
     }
 
     override val self: ArrayVector<T> get() = this
 
     override fun iterator(): Iterator<T> = (0 until size).map { array[it] }.iterator()
 
-    override fun toString(): String = this.joinToString(prefix = "[",postfix = "]", separator = ", "){it.toString()}
+    override fun copy(): ArrayVector<T> = ArrayVector(context, array)
+
+    override fun toString(): String = this.joinToString(prefix = "[", postfix = "]", separator = ", ") { it.toString() }
 }
 
 typealias RealVector = Vector<Double>

kmath-core/src/commonMain/kotlin/scientifik/kmath/structures/Buffers.kt

@@ -4,7 +4,7 @@ package scientifik.kmath.structures
 /**
  * A generic linear buffer for both primitives and objects
  */
-interface Buffer<T> {
+interface Buffer<T> : Iterable<T> {
 
     val size: Int
 
@@ -36,6 +36,8 @@ inline class ListBuffer<T>(private val list: MutableList<T>) : MutableBuffer<T>
         list[index] = value
     }
 
+    override fun iterator(): Iterator<T>  = list.iterator()
+
     override fun copy(): MutableBuffer<T> = ListBuffer(ArrayList(list))
 }
 
@@ -49,6 +51,8 @@ class ArrayBuffer<T>(private val array: Array<T>) : MutableBuffer<T> {
         array[index] = value
     }
 
+    override fun iterator(): Iterator<T>  = array.iterator()
+
     override fun copy(): MutableBuffer<T> = ArrayBuffer(array.copyOf())
 }
 
@@ -62,6 +66,8 @@ class DoubleBuffer(private val array: DoubleArray) : MutableBuffer<Double> {
         array[index] = value
     }
 
+    override fun iterator(): Iterator<Double>  = array.iterator()
+
     override fun copy(): MutableBuffer<Double> = DoubleBuffer(array.copyOf())
 }
 

kmath-core/src/jvmMain/kotlin/scientifik/kmath/histogram/UnivariateHistogram.kt

@@ -2,6 +2,7 @@ package scientifik.kmath.histogram
 
 import scientifik.kmath.linear.RealVector
 import scientifik.kmath.linear.toVector
+import scientifik.kmath.structures.Buffer
 import java.util.*
 import kotlin.math.floor
 
@@ -15,7 +16,7 @@ class UnivariateBin(val position: Double, val size: Double, val counter: LongCou
 
     operator fun contains(value: Double): Boolean = value in (position - size / 2)..(position + size / 2)
 
-    override fun contains(vector: RealVector): Boolean = contains(vector[0])
+    override fun contains(vector: Buffer<out Double>): Boolean = contains(vector[0])
 
     internal operator fun inc() = this.also { counter.increment()}
 
@@ -44,7 +45,7 @@ class UnivariateHistogram private constructor(private val factory: (Double) -> U
         synchronized(this) { bins.put(it.position, it) }
     }
 
-    override fun get(point: RealVector): UnivariateBin? = get(point[0])
+    override fun get(point: Buffer<out Double>): UnivariateBin? = get(point[0])
 
     override val dimension: Int get() = 1
 
@@ -57,7 +58,7 @@ class UnivariateHistogram private constructor(private val factory: (Double) -> U
         (get(value) ?: createBin(value)).inc()
     }
 
-    override fun put(point: RealVector) = put(point[0])
+    override fun put(point: Buffer<out Double>) = put(point[0])
 
     companion object {
         fun uniform(binSize: Double, start: Double = 0.0): UnivariateHistogram {