fix _compute_fans when more than 4 dimensions.

Author: Oceania2018

src/TensorFlowNET.Core/Keras/Engine/Layer.cs

@@ -57,5 +57,21 @@ protected virtual void build(TensorShape input_shape)
         {
 
         }
+
+        protected virtual void add_weight(string name,
+            int[] shape,
+            TF_DataType dtype = TF_DataType.DtInvalid,
+            IInitializer initializer = null,
+            bool? trainable = null,
+            Func<string, int[], TF_DataType, IInitializer, bool, RefVariable> getter = null)
+        {
+            _add_variable_with_custom_getter(name,
+                shape,
+                dtype: dtype,
+                getter: getter,
+                overwrite: true,
+                initializer: initializer,
+                trainable: trainable.Value);
+        }
     }
 }

src/TensorFlowNET.Core/Keras/Layers/Conv.cs

@@ -53,7 +53,11 @@ protected override void build(TensorShape input_shape)
             int channel_axis = data_format == "channels_first" ? 1 : -1;
             int input_dim = input_shape.Dimensions[input_shape.NDim - 1];
             var kernel_shape = new int[] { kernel_size[0], kernel_size[1], input_dim, filters };
-            add_weight();
+            add_weight(name: "kernel", 
+                shape: kernel_shape,
+                initializer: kernel_initializer,
+                trainable: true,
+                dtype: _dtype);
         }
     }
 }

src/TensorFlowNET.Core/Layers/Layer.cs

@@ -68,7 +68,11 @@ public Tensor __call__(Tensor inputs,
             throw new NotImplementedException("");
         }
 
-        protected virtual void add_weight()
+        protected virtual void add_weight(string name,
+            int[] shape,
+            TF_DataType dtype = TF_DataType.DtInvalid,
+            IInitializer initializer = null,
+            bool? trainable = null)
         {
             var default_graph = ops.get_default_graph();
             Graph init_graph = null;
@@ -84,7 +88,9 @@ protected virtual void add_weight()
                 existing_variables = variables.global_variables().ToArray();
             }
 
-            var dtype = TF_DataType.TF_FLOAT;
+            if(dtype == TF_DataType.DtInvalid)
+                dtype = TF_DataType.TF_FLOAT;
+
             _set_scope();
             var reuse = built || (_reuse != null && _reuse.Value);
             Python.with(tf.variable_scope(_scope, 
@@ -94,8 +100,19 @@ protected virtual void add_weight()
                 _current_scope = scope;
                 Python.with(ops.name_scope(_name_scope()), delegate
                 {
-
-
+                    base.add_weight(name,
+                        shape,
+                        dtype: dtype,
+                        initializer: initializer,
+                        trainable: trainable,
+                        getter: (name1, shape1, dtype1, initializer1, trainable1) =>
+                        {
+                            return tf.get_variable(name1, 
+                                shape: new TensorShape(shape1),
+                                dtype: dtype1,
+                                initializer: initializer1,
+                                trainable: trainable1);
+                        });
                 });
             });
         }

src/TensorFlowNET.Core/Operations/Initializers/VarianceScaling.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using System.Text;
 
 namespace Tensorflow.Operations.Initializers
@@ -64,7 +65,16 @@ public Tensor call(TensorShape shape, TF_DataType dtype)
             if (shape.Length == 2)
                 return (shape[0], shape[1]);
             else
-                throw new NotImplementedException("VarianceScaling._compute_fans");
+            {
+                // Assuming convolution kernels (2D, 3D, or more).
+                // kernel shape: (..., input_depth, depth)
+                int receptive_field_size = 1;
+                foreach (var dim in shape.Take(2))
+                    receptive_field_size *= dim;
+                var fan_in = shape[shape.Length - 2] * receptive_field_size;
+                var fan_out = shape[shape.Length - 1] * receptive_field_size;
+                return (fan_in, fan_out);
+            }
         }
 
         public virtual object get_config()

src/TensorFlowNET.Core/Train/Checkpointable/CheckpointableBase.cs

@@ -4,7 +4,22 @@
 
 namespace Tensorflow
 {
-    public class CheckpointableBase
+    public abstract class CheckpointableBase
     {
+        /// <summary>
+        /// Restore-on-create for a variable be saved with this `Checkpointable`.
+        /// </summary>
+        /// <returns></returns>
+        protected virtual RefVariable _add_variable_with_custom_getter(string name,
+            int[] shape,
+            TF_DataType dtype = TF_DataType.TF_FLOAT,
+            IInitializer initializer = null,
+            Func<string, int[], TF_DataType, IInitializer, bool, RefVariable> getter = null,
+            bool overwrite = false,
+            bool trainable = false)
+        {
+            var new_variable = getter(name, shape, dtype, initializer, trainable);
+            throw new NotImplementedException("_add_variable_with_custom_getter");
+        }
     }
 }

src/TensorFlowNET.Core/Variables/VariableScope.cs

@@ -48,6 +48,7 @@ public RefVariable get_variable(_VariableStore var_store,
                     shape: shape, 
                     dtype: dtype,
                     initializer: initializer,
+                    reuse: resue,
                     trainable: trainable,
                     synchronization: synchronization,
                     aggregation: aggregation);

src/TensorFlowNET.Core/Variables/_VariableStore.cs

@@ -24,6 +24,7 @@ public RefVariable get_variable(string name,
             TensorShape shape = null,
             TF_DataType dtype = TF_DataType.TF_FLOAT,
             object initializer = null, // IInitializer or Tensor
+            bool? reuse = null,
             bool? trainable = null,
             bool validate_shape = true,
             VariableSynchronization synchronization = VariableSynchronization.AUTO,
@@ -100,7 +101,7 @@ private RefVariable _get_single_variable(string name,
             VariableSynchronization synchronization = VariableSynchronization.AUTO,
             VariableAggregation aggregation = VariableAggregation.NONE)
         {
-            bool initializing_from_value = true;
+            bool initializing_from_value = false;
             if (use_resource == null)
                 use_resource = false;