Examples for type-safe dimensions

examples/build.gradle.kts

@@ -5,7 +5,7 @@ plugins {
     java
     kotlin("jvm")
     kotlin("plugin.allopen") version "1.3.61"
-    id("kotlinx.benchmark") version "0.2.0-dev-5"
+    id("kotlinx.benchmark") version "0.2.0-dev-7"
 }
 
 configure<AllOpenExtension> {
@@ -13,10 +13,7 @@ configure<AllOpenExtension> {
 }
 
 repositories {
-    maven("https://dl.bintray.com/kotlin/kotlin-eap")
     maven("http://dl.bintray.com/kyonifer/maven")
-    maven ("https://dl.bintray.com/orangy/maven")
-
     mavenCentral()
 }
 
@@ -30,12 +27,10 @@ dependencies {
     implementation(project(":kmath-commons"))
     implementation(project(":kmath-koma"))
     implementation(project(":kmath-viktor"))
+    implementation(project(":kmath-dimensions"))
     implementation("com.kyonifer:koma-core-ejml:0.12")
     implementation("org.jetbrains.kotlinx:kotlinx-io-jvm:${Scientifik.ioVersion}")
-
+    implementation("org.jetbrains.kotlinx:kotlinx.benchmark.runtime:0.2.0-dev-7")
-    implementation("org.jetbrains.kotlinx:kotlinx.benchmark.runtime:0.2.0-dev-2")
-
-
     "benchmarksCompile"(sourceSets.main.get().compileClasspath)
 }
 

examples/src/benchmarks/kotlin/scientifik/kmath/structures/ViktorBenchmark.kt

@@ -1,28 +1,26 @@
 package scientifik.kmath.structures
 
 import org.jetbrains.bio.viktor.F64Array
+import org.openjdk.jmh.annotations.Benchmark
+import org.openjdk.jmh.annotations.Scope
+import org.openjdk.jmh.annotations.State
 import scientifik.kmath.operations.RealField
 import scientifik.kmath.viktor.ViktorNDField
 
 
-fun main() {
+@State(Scope.Benchmark)
-    val dim = 1000
+class ViktorBenchmark {
-    val n = 400
+    final val dim = 1000
+    final val n = 100
 
     // automatically build context most suited for given type.
-    val autoField = NDField.auto(RealField, dim, dim)
+    final val autoField = NDField.auto(RealField, dim, dim)
-    val realField = NDField.real(dim,dim)
+    final val realField = NDField.real(dim, dim)
 
-    val viktorField = ViktorNDField(intArrayOf(dim, dim))
+    final val viktorField = ViktorNDField(intArrayOf(dim, dim))
 
-    autoField.run {
+    @Benchmark
-        var res = one
+    fun `Automatic field addition`() {
-        repeat(n/2) {
-            res += 1.0
-        }
-    }
-
-    measureAndPrint("Automatic field addition") {
         autoField.run {
             var res = one
             repeat(n) {
@@ -31,14 +29,8 @@ fun main() {
         }
     }
 
-    viktorField.run {
+    @Benchmark
-        var res = one
+    fun `Viktor field addition`() {
-        repeat(n/2) {
-            res += one
-        }
-    }
-
-    measureAndPrint("Viktor field addition") {
         viktorField.run {
             var res = one
             repeat(n) {
@@ -47,7 +39,8 @@ fun main() {
         }
     }
 
-    measureAndPrint("Raw Viktor") {
+    @Benchmark
+    fun `Raw Viktor`() {
         val one = F64Array.full(init = 1.0, shape = *intArrayOf(dim, dim))
         var res = one
         repeat(n) {
@@ -55,7 +48,8 @@ fun main() {
         }
     }
 
-    measureAndPrint("Automatic field log") {
+    @Benchmark
+    fun `Real field log`() {
         realField.run {
             val fortyTwo = produce { 42.0 }
             var res = one
@@ -66,7 +60,8 @@ fun main() {
         }
     }
 
-    measureAndPrint("Raw Viktor log") {
+    @Benchmark
+    fun `Raw Viktor log`() {
         val fortyTwo = F64Array.full(dim, dim, init = 42.0)
         var res: F64Array
         repeat(n) {

examples/src/benchmarks/kotlin/scientifik/kmath/utils/utils.kt

@@ -0,0 +1,8 @@
+package scientifik.kmath.utils
+
+import kotlin.system.measureTimeMillis
+
+internal inline fun measureAndPrint(title: String, block: () -> Unit) {
+    val time = measureTimeMillis(block)
+    println("$title completed in $time millis")
+}

examples/src/main/kotlin/scientifik/kmath/structures/typeSafeDimensions.kt

@@ -0,0 +1,34 @@
+package scientifik.kmath.structures
+
+import scientifik.kmath.dimensions.D2
+import scientifik.kmath.dimensions.D3
+import scientifik.kmath.dimensions.DMatrixContext
+import scientifik.kmath.dimensions.Dimension
+import scientifik.kmath.operations.RealField
+
+fun DMatrixContext<Double, RealField>.simple() {
+    val m1 = produce<D2, D3> { i, j -> (i + j).toDouble() }
+    val m2 = produce<D3, D2> { i, j -> (i + j).toDouble() }
+
+    //Dimension-safe addition
+    m1.transpose() + m2
+}
+
+object D5: Dimension{
+    override val dim: UInt = 5u
+}
+
+fun DMatrixContext<Double, RealField>.custom() {
+    val m1 = produce<D2, D5> { i, j -> (i+j).toDouble() }
+    val m2 = produce<D5,D2> { i, j -> (i-j).toDouble() }
+    val m3 = produce<D2,D2> { i, j -> (i-j).toDouble() }
+
+    (m1 dot m2) + m3
+}
+
+fun main() {
+    DMatrixContext.real.run {
+        simple()
+        custom()
+    }
+}

kmath-dimensions/build.gradle.kts

@@ -1,5 +1,5 @@
 plugins {
-    `npm-multiplatform`
+    id("scientifik.mpp")
 }
 
 description = "A proof of concept module for adding typ-safe dimensions to structures"

kmath-dimensions/src/commonMain/kotlin/scientifik/kmath/dimensions/Dimensions.kt

@@ -1,9 +1,14 @@
 package scientifik.kmath.dimensions
 
+/**
+ * An interface which is not used in runtime. Designates a size of some structure.
+ * All descendants should be singleton objects.
+ */
 interface Dimension {
     val dim: UInt
 
     companion object {
+        @Suppress("NOTHING_TO_INLINE")
         inline fun of(dim: UInt): Dimension {
             return when (dim) {
                 1u -> D1
@@ -15,8 +20,8 @@ interface Dimension {
             }
         }
 
-        inline fun <reified D: Dimension> dim(): UInt{
+        inline fun <reified D : Dimension> dim(): UInt {
-            return D::class.objectInstance!!.dim
+            return D::class.objectInstance?.dim ?: error("Dimension object must be a singleton")
         }
     }
 }

kmath-dimensions/src/commonMain/kotlin/scientifik/kmath/dimensions/Wrappers.kt

@@ -8,14 +8,21 @@ import scientifik.kmath.operations.Ring
 import scientifik.kmath.structures.Matrix
 import scientifik.kmath.structures.Structure2D
 
+/**
+ * A matrix with compile-time controlled dimension
+ */
 interface DMatrix<T, R : Dimension, C : Dimension> : Structure2D<T> {
     companion object {
         /**
          * Coerces a regular matrix to a matrix with type-safe dimensions and throws a error if coercion failed
          */
         inline fun <T, reified R : Dimension, reified C : Dimension> coerce(structure: Structure2D<T>): DMatrix<T, R, C> {
-            if (structure.rowNum != Dimension.dim<R>().toInt()) error("Row number mismatch: expected ${Dimension.dim<R>()} but found ${structure.rowNum}")
+            if (structure.rowNum != Dimension.dim<R>().toInt()) {
-            if (structure.colNum != Dimension.dim<C>().toInt()) error("Column number mismatch: expected ${Dimension.dim<C>()} but found ${structure.colNum}")
+                error("Row number mismatch: expected ${Dimension.dim<R>()} but found ${structure.rowNum}")
+            }
+            if (structure.colNum != Dimension.dim<C>().toInt()) {
+                error("Column number mismatch: expected ${Dimension.dim<C>()} but found ${structure.colNum}")
+            }
             return DMatrixWrapper(structure)
         }
 
@@ -28,6 +35,9 @@ interface DMatrix<T, R : Dimension, C : Dimension> : Structure2D<T> {
     }
 }
 
+/**
+ * An inline wrapper for a Matrix
+ */
 inline class DMatrixWrapper<T, R : Dimension, C : Dimension>(
     val structure: Structure2D<T>
 ) : DMatrix<T, R, C> {
@@ -35,10 +45,15 @@ inline class DMatrixWrapper<T, R : Dimension, C : Dimension>(
     override fun get(i: Int, j: Int): T = structure[i, j]
 }
 
+/**
+ * Dimension-safe point
+ */
 interface DPoint<T, D : Dimension> : Point<T> {
     companion object {
         inline fun <T, reified D : Dimension> coerce(point: Point<T>): DPoint<T, D> {
-            if (point.size != Dimension.dim<D>().toInt()) error("Vector dimension mismatch: expected ${Dimension.dim<D>()}, but found ${point.size}")
+            if (point.size != Dimension.dim<D>().toInt()) {
+                error("Vector dimension mismatch: expected ${Dimension.dim<D>()}, but found ${point.size}")
+            }
             return DPointWrapper(point)
         }
 
@@ -48,6 +63,9 @@ interface DPoint<T, D : Dimension> : Point<T> {
     }
 }
 
+/**
+ * Dimension-safe point wrapper
+ */
 inline class DPointWrapper<T, D : Dimension>(val point: Point<T>) : DPoint<T, D> {
     override val size: Int get() = point.size
 
@@ -58,7 +76,7 @@ inline class DPointWrapper<T, D : Dimension>(val point: Point<T>) : DPoint<T, D>
 
 
 /**
- * Basic operations on matrices. Operates on [Matrix]
+ * Basic operations on dimension-safe matrices. Operates on [Matrix]
  */
 inline class DMatrixContext<T : Any, Ri : Ring<T>>(val context: GenericMatrixContext<T, Ri>) {