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

@@ -0,0 +1,20 @@
+package scientifik.kmath.structures
+
+//
+//class LazyStructureField<T: Any>(val field: Field<T>): Field<LazyStructure<T>>{
+//
+//}
+//
+//class LazyStructure<T : Any> : NDStructure<T> {
+//
+//    override val shape: IntArray
+//        get() = TODO("not implemented") //To change initializer of created properties use File | Settings | File Templates.
+//
+//    override fun get(index: IntArray): T {
+//        TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
+//    }
+//
+//    override fun iterator(): Iterator<Pair<IntArray, T>> {
+//        TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
+//    }
+//}

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

@@ -1,6 +1,5 @@
 package scientifik.kmath.structures
 
-import scientifik.kmath.operations.DoubleField
 import scientifik.kmath.operations.Field
 import scientifik.kmath.operations.FieldElement
 
@@ -107,14 +106,15 @@ abstract class NDField<T>(val shape: IntArray, val field: Field<T>) : Field<NDAr
 /**
  *  Immutable [NDStructure] coupled to the context. Emulates Python ndarray
  */
-data class NDArray<T>(override val context: NDField<T>, private val structure: NDStructure<T>) : FieldElement<NDArray<T>, NDField<T>>, NDStructure<T> by structure {
+class NDArray<T>(override val context: NDField<T>, private val structure: NDStructure<T>) : FieldElement<NDArray<T>, NDField<T>>, NDStructure<T> by structure {
 
     //TODO ensure structure is immutable
 
     override val self: NDArray<T>
         get() = this
 
-    fun transform(action: (IntArray, T) -> T): NDArray<T> = context.produce { action(it, get(*it)) }
+    inline fun transform(crossinline action: (IntArray, T) -> T): NDArray<T> = context.produce { action(it, get(*it)) }
+    inline fun transform(crossinline action: (T) -> T): NDArray<T> = context.produce { action(get(*it)) }
 }
 
 /**
@@ -173,7 +173,7 @@ object NDArrays {
      * Create a platform-optimized NDArray of doubles
      */
     fun realNDArray(shape: IntArray, initializer: (IntArray) -> Double = { 0.0 }): NDArray<Double> {
-        return GenericNDField(shape, DoubleField).produce(initializer)
+        return RealNDField(shape).produce(initializer)
     }
 
     fun real1DArray(dim: Int, initializer: (Int) -> Double = { _ -> 0.0 }): NDArray<Double> {
@@ -188,6 +188,8 @@ object NDArrays {
         return realNDArray(intArrayOf(dim1, dim2, dim3)) { initializer(it[0], it[1], it[2]) }
     }
 
+    inline fun produceReal(shape: IntArray, block: RealNDField.() -> RealNDArray) = RealNDField(shape).run(block)
+
 //    /**
 //     * Simple boxing NDField
 //     */

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

@@ -0,0 +1,46 @@
+package scientifik.kmath.structures
+
+import scientifik.kmath.operations.DoubleField
+import scientifik.kmath.operations.ExponentialOperations
+import scientifik.kmath.operations.PowerOperations
+import scientifik.kmath.operations.TrigonometricOperations
+import kotlin.math.*
+
+typealias RealNDArray = NDArray<Double>
+
+
+class RealNDField(shape: IntArray) : NDField<Double>(shape, DoubleField),
+        TrigonometricOperations<RealNDArray>,
+        PowerOperations<RealNDArray>,
+        ExponentialOperations<RealNDArray> {
+
+    override fun produceStructure(initializer: (IntArray) -> Double): NDStructure<Double> {
+        return genericNdStructure(shape, initializer)
+    }
+
+    override fun power(arg: RealNDArray, pow: Double): RealNDArray {
+        return arg.transform { d -> d.pow(pow) }
+    }
+
+    override fun exp(arg: RealNDArray): RealNDArray {
+        return arg.transform { d -> exp(d) }
+    }
+
+    override fun ln(arg: RealNDArray): RealNDArray {
+        return arg.transform { d -> ln(d) }
+    }
+
+    override fun sin(arg: RealNDArray): RealNDArray {
+        return arg.transform { d -> sin(d) }
+    }
+
+    override fun cos(arg: RealNDArray): RealNDArray {
+        return arg.transform { d -> cos(d) }
+    }
+
+    fun abs(arg: RealNDArray): RealNDArray {
+        return arg.transform { d -> abs(d) }
+    }
+}
+
+

kmath-core/src/commonTest/kotlin/scientifik/kmath/expressions/FieldExpressionContextTest.kt

@@ -39,4 +39,15 @@ class FieldExpressionContextTest {
         val expression = FieldExpressionContext(DoubleField).expression()
         assertEquals(expression("x" to 1.0), 4.0)
     }
+
+    @Test
+    fun valueExpression() {
+        val expressionBuilder: FieldExpressionContext<Double>.()->Expression<Double> = {
+            val x = variable("x")
+            x * x + 2 * x + 1.0
+        }
+
+        val expression = FieldExpressionContext(DoubleField).expressionBuilder()
+        assertEquals(expression("x" to 1.0), 4.0)
+    }
 }

kmath-core/src/commonTest/kotlin/scientifik/kmath/structures/RealNDFieldTest.kt

@@ -1,6 +1,8 @@
 package scientifik.kmath.structures
 
+import scientifik.kmath.structures.NDArrays.produceReal
 import scientifik.kmath.structures.NDArrays.real2DArray
+import kotlin.math.abs
 import kotlin.math.pow
 import kotlin.test.Test
 import kotlin.test.assertEquals
@@ -40,4 +42,18 @@ class RealNDFieldTest {
         val result = function(array1) + 1.0
         assertEquals(10.0, result[1,1])
     }
+
+    @Test
+    fun testLibraryFunction() {
+        val abs: (Double) -> Double = ::abs
+        val result = abs(array1)
+        assertEquals(10.0, result[1,1])
+    }
+
+    @Test
+    fun testAbs(){
+        val res = produceReal(array1.shape){
+           1 + abs(array1) + exp(array2)
+        }
+    }
 }