Some sugar

Signed-off-by: Alexander Stoyakin <alexander.stoyakin@gmail.com>

nd4s/src/main/scala/org/nd4s/samediff/SameDiff.scala

@@ -54,10 +54,21 @@ class SameDiffWrapper {
     sd.placeHolder(name, dataType, shape: _*)
 }
 
+case class SDIndexWrapper(start: Long) {
+
+  def ::(end: Long): SDIndex =
+    SDIndex.interval(start, end)
+}
+
+object --- extends SDIndex {
+  val thisIndex: SDIndex = SDIndex.all()
+}
+
 class SDVariableWrapper {
 
   var thisVariable: SDVariable = null
   var isScalar: Boolean = false
+  val --- : SDIndex = SDIndex.all()
 
   def this(variable: SDVariable) {
     this
@@ -68,13 +79,13 @@ class SDVariableWrapper {
 
   def apply(index: SDIndex*): SDVariable = thisVariable.get(index: _*)
 
-  def apply(x: SDIndex)(y: SDIndex): SDVariable =
+  /*def apply(x: SDIndex, y: SDIndex): SDVariable =
     (x, y) match {
       case (_, y) => thisVariable.get(SDIndex.all(), y)
       case (x, _) => thisVariable.get(x, SDIndex.all())
       case (_, _) => thisVariable.get(SDIndex.all(), SDIndex.all())
       case (x, y) => thisVariable.get(x, y)
-    }
+    }*/
 
   def add(other: Double): Unit = thisVariable.add(other)
 

nd4s/src/main/scala/org/nd4s/samediff/implicits/Implicits.scala

@@ -15,9 +15,9 @@
   ******************************************************************************/
 package org.nd4s.samediff.implicits
 
-import org.nd4j.autodiff.samediff.{ SDVariable, SameDiff }
+import org.nd4j.autodiff.samediff.{ SDIndex, SDVariable, SameDiff }
 import org.nd4j.linalg.factory.Nd4j
-import org.nd4s.samediff.{ SDVariableWrapper, SameDiffWrapper }
+import org.nd4s.samediff.{ SDIndexWrapper, SDVariableWrapper, SameDiffWrapper }
 
 object Implicits {
   implicit def SameDiffToWrapper(sd: SameDiff): SameDiffWrapper =
@@ -43,4 +43,9 @@ object Implicits {
     result.isScalar = true
     result
   }
+
+  implicit def RangeToWrapper(start: Long): SDIndexWrapper = {
+    val result = new SDIndexWrapper(start)
+    result
+  }
 }

nd4s/src/test/scala/org/nd4s/samediff/MathTest.scala

@@ -20,6 +20,7 @@ import org.nd4j.linalg.api.buffer.DataType
 import org.nd4j.linalg.api.ndarray.INDArray
 import org.nd4j.linalg.factory.Nd4j
 import org.nd4s.Implicits._
+import org.nd4s.NDOrdering
 import org.nd4s.samediff.implicits.Implicits._
 import org.scalatest.{ FlatSpec, Matchers }
 
@@ -214,9 +215,20 @@ class MathTest extends FlatSpec with Matchers {
   "SDVariable " should "be indexable in 2d" in {
     implicit val sd = SameDiff.create
 
-    val arr = Nd4j.rand(2, 5)
+    val arr = Nd4j.linspace(DataType.FLOAT, 1.0, 1.0, 9).reshape(3, 3)
+
     val x = sd.bind(arr)
 
-    println(x(SDIndex.point(0), _: SDIndex).getArr)
+    println(x(SDIndex.point(0), ---).getArr)
+
+    val data1 = x(SDIndex.interval(0: Long, 2: Long), ---).getArr
+    println(data1)
+
+    val data2 = x(0 :: 2, ---).getArr
+    println(data2)
+
+    //assert(indices.indices == List(0, 1, 2, 3, 4, 5))
+    //assert(indices.targetShape.toList == List(2, 3))
+
   }
 }