Fix Gather op

Author: EmergentOrder

core/src/main/scala/ONNX.scala

@@ -429,20 +429,21 @@ package object onnx {
     }
   }
   //Missing in NDScala - P3
+  //need a match type
   trait GatherV13 extends Operator {
     def GatherV13[
         @sp T <: UByte | UShort | UInt | ULong | Byte | Short | Int | Long | BFloat16 | Float16 | Float | Double | String | Boolean | Complex[
           Float
-        ] | Complex[Double]: Numeric,
-        @sp Tind <: Int | Long: Numeric
-    , Tt <: TensorTypeDenotation, Td <: TensorShapeDenotation, S <: Shape, Tt1 <: TensorTypeDenotation, Td1 <: TensorShapeDenotation, S1 <: Shape, Tt2 <: TensorTypeDenotation, Td2 <: TensorShapeDenotation, S2 <: Shape](
+        ] | Complex[Double],
+        @sp Tind <: Int : Numeric, //Spec also supports long
+     Tt <: TensorTypeDenotation, Td <: TensorShapeDenotation, S <: Shape, Tt1 <: TensorTypeDenotation, Td1 <: TensorShapeDenotation, S1 <: Shape, Tt2 <: TensorTypeDenotation, Td2 <: TensorShapeDenotation, AxisIndex <: Index ::: INil, AxisIndices <: Indices](
         name: String,
-        axis: Int = 0,
+        axis: AxisIndex = 0 ::: INil,
         data: Tensor[T, Tuple3[Tt,Td,S]],
-        indices: Tensor[Tind, Tuple3[Tt1,Td1,S1]]
-    )(using tt: ValueOf[Tt2], td: TensorShapeDenotationOf[Td2], s: ShapeOf[S2]): Tensor[T, Tuple3[Tt2,Td2,S2]] = {
-      val map: Map[String, Any] = Map("axis" -> axis)
-      val allInputs             = Tuple2(data, indices)
+        indices: AxisIndices
+    )(using tt: ValueOf[Tt2], td: TensorShapeDenotationOf[Td2], s: ShapeOf[GatheredShape[S, AxisIndex, AxisIndices]], i: IndicesOf[AxisIndex], i2: IndicesOf[AxisIndices]): Tensor[T, Tuple3[Tt2,Td2,GatheredShape[S, AxisIndex, AxisIndices]]] = {
+      val map: Map[String, Any] = Map("axis" -> indicesOf[AxisIndex].indices.toArray.head)
+      val allInputs             = Tuple2(data, Tensor(indicesOf[AxisIndices].indices.toArray, indicesOf[AxisIndices].indices.toArray.size.asInstanceOf[io.kjaer.compiletime.Dimension] #: SNil))
       (callOp(name, "Gather", allInputs, map))
     }
   }

core/src/main/scala/Tensors.scala

@@ -97,6 +97,27 @@ object Tensors{
     }
   }
 
+  type GatheredShape[S <: Shape, AxisIndex <: None.type | Indices, AxisIndices <: Indices] <: Shape = AxisIndex match {
+    case None.type => SNil
+    case Indices => GatheredShapeLoop[S, AxisIndex, 0, AxisIndices]
+  }
+
+  protected type GatheredShapeLoop[ToGather <: Shape, AxisIndex <: Indices, I <: Index, AxisIndices <: Indices] <: Shape = ToGather match {
+    case head #: tail => Indices.Contains[AxisIndex, I] match {
+      case true => IndicesSize[AxisIndices] #: GatheredShapeLoop[tail, Indices.RemoveValue[AxisIndex, I], S[I], AxisIndices]
+      case false => head #: GatheredShapeLoop[tail, AxisIndex, S[I], AxisIndices]
+    }
+    case SNil => AxisIndex match {
+      case INil => SNil
+    }
+  }
+
+  type IndicesSize[AxisIndices <: Indices] = IndicesSizeLoop[AxisIndices, 0]
+
+  type IndicesSizeLoop[AxisIndices <: Indices, Acc <: Dimension] = AxisIndices match {
+    case head ::: tail => IndicesSizeLoop[tail, S[Acc]]
+    case INil => Acc
+  }
 
  type FlattenedShape[S <: Shape, AxisIndex <: None.type | Indices] <: Shape = AxisIndex match {
     case None.type => SNil