fix array_ops.slice #646

Author: Oceania2018

src/TensorFlowNET.Core/Operations/array_ops.cs

@@ -812,6 +812,9 @@ private static Tensor[] split_eager_fallback<Ta, Tv>(Ta axis, Tv value, int num_
             return tf.Runner.Execute(ctx, "Split", num_split, _inputs_flat.ToArray(), _attrs, name: name);
         }
 
+        public static Tensor slice(Tensor input, Tensor[] begin, Tensor[] size, string name = null)
+            => gen_array_ops.slice(input, begin, size, name: name);
+
         public static Tensor slice<Tb, Ts>(Tensor input, Tb begin, Ts size, string name = null)
             => gen_array_ops.slice(input, begin, size, name: name);
 

src/TensorFlowNET.Core/Operations/gen_array_ops.cs

@@ -14,6 +14,7 @@ You may obtain a copy of the License at
    limitations under the License.
 ******************************************************************************/
 
+using System;
 using System.Linq;
 using Tensorflow.Contexts;
 using static Tensorflow.Binding;
@@ -448,15 +449,34 @@ public static Tensor size(Tensor input, TF_DataType out_type = TF_DataType.TF_IN
             return _op.outputs[0];
         }
 
-        /// <summary>
-        /// Return a slice from 'input'
-        /// </summary>
-        /// <param name="input"></param>
-        /// <param name="begin"></param>
-        /// <param name="size"></param>
-        /// <param name="name"></param>
-        /// <returns></returns>
-        public static Tensor slice(Tensor input, Tensor begin, Tensor size, string name = null)
+        public static Tensor slice(Tensor input, Tensor[] begin, Tensor[] size, string name = null)
+        {
+            if (tf.executing_eagerly())
+            {
+                var result = slice_eager_fallback(input, begin, size, name, tf.Context);
+                return result;
+            }
+
+            var _op = tf.OpDefLib._apply_op_helper("Slice", name, new { input, begin, size });
+            return _op.outputs[0];
+        }
+
+        private static Tensor slice_eager_fallback(Tensor inputs, Tensor[] begin, Tensor[] size, string name, Context ctx)
+        {
+            var (_attr_T, input) = tf.Runner.ArgsToMatchingEager(ctx, args: new[] { inputs });
+            var (_attr_Tidx, _inputs_Index) = tf.Runner.ArgsToMatchingEager(ctx, args: new object[] { begin, size });
+            var _inputs_flat = input.concat(_inputs_Index);
+            var _attrs = new object[] { "T", _attr_T, "Index", _attr_Tidx };
+
+            var results = tf.Runner.Execute(ctx, "Slice", 1, _inputs_flat, _attrs, name: name);
+            if (tf.Runner.MustRecordGradient())
+            {
+                tf.Runner.RecordGradient("Slice", _inputs_flat, _attrs, results);
+            }
+            return results[0];
+        }
+
+        public static Tensor slice<Tb, Ts>(Tensor input, Tb begin, Ts size, string name = null)
         {
             var _op = tf.OpDefLib._apply_op_helper("Slice", name, new { input, begin, size });
             return _op.outputs[0];
@@ -605,12 +625,6 @@ public static Tensor strided_slice_grad(Tensor shape, Tensor begin, Tensor end,
                     "shrink_axis_mask", shrink_axis_mask).FirstOrDefault(),
                 shape, begin, end, strides, dy);
 
-        public static Tensor slice<Tb, Ts>(Tensor input, Tb begin, Ts size, string name = null)
-        {
-            var _op = tf.OpDefLib._apply_op_helper("Slice", name, new { input, begin, size });
-            return _op.outputs[0];
-        }
-
         /// <summary>
         /// Removes dimensions of size 1 from the shape of a tensor.
         /// Given a tensor `input`, this operation returns a tensor of the same type with