add SafeTensorHandle to manage tensor handle reference.

Author: Oceania2018

src/TensorFlowNET.Console/Tensorflow.Console.csproj

@@ -19,7 +19,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="SciSharp.TensorFlow.Redist-Windows-GPU" Version="2.5.0" />
+    <PackageReference Include="SciSharp.TensorFlow.Redist" Version="2.5.0" />
   </ItemGroup>
 
   <ItemGroup>

src/TensorFlowNET.Core/Attributes/c_api.ops.cs

@@ -99,7 +99,7 @@ public partial class c_api
         public static extern void TF_SetAttrStringList(IntPtr desc, string attr_name, IntPtr[] values, uint[] lengths, int num_values);
 
         [DllImport(TensorFlowLibName)]
-        public static extern void TF_SetAttrTensor(IntPtr desc, string attr_name, IntPtr value, SafeStatusHandle status);
+        public static extern void TF_SetAttrTensor(IntPtr desc, string attr_name, SafeTensorHandle value, SafeStatusHandle status);
 
         [DllImport(TensorFlowLibName)]
         public static extern void TF_SetAttrType(IntPtr desc, string attr_name, TF_DataType value);

src/TensorFlowNET.Core/Binding.Util.cs

@@ -164,8 +164,6 @@ public static int len(object a)
                     return arr.Count;
                 case ICollection arr:
                     return arr.Count;
-                case NDArray ndArray:
-                    return ndArray.ndim == 0 ? 1 : (int)ndArray.dims[0];
                 case IEnumerable enumerable:
                     return enumerable.OfType<object>().Count();
                 case Shape arr:

src/TensorFlowNET.Core/Data/MnistDataSet.cs

@@ -10,7 +10,7 @@ public class MnistDataSet : DataSetBase
         public int EpochsCompleted { get; private set; }
         public int IndexInEpoch { get; private set; }
 
-        public MnistDataSet(NDArray images, NDArray labels, Type dataType, bool reshape)
+        public MnistDataSet(NDArray images, NDArray labels, TF_DataType dataType, bool reshape)
         {
             EpochsCompleted = 0;
             IndexInEpoch = 0;

src/TensorFlowNET.Core/Data/ModelLoadSetting.cs

@@ -6,7 +6,7 @@ public class ModelLoadSetting
     {
         public string TrainDir { get; set; }
         public bool OneHot { get; set; }
-        public Type DataType { get; set; } = typeof(float);
+        public TF_DataType DataType { get; set; } = TF_DataType.TF_FLOAT;
         public bool ReShape { get; set; }
         public int ValidationSize { get; set; } = 5000;
         public int? TrainSize { get; set; }

src/TensorFlowNET.Core/DisposableObject.cs

@@ -48,7 +48,7 @@ private void Dispose(bool disposing)
             }
 
             // free unmanaged memory
-            if (_handle != IntPtr.Zero)
+            // if (_handle != IntPtr.Zero)
             {
                 // Call the appropriate methods to clean up
                 // unmanaged resources here.

src/TensorFlowNET.Core/Eager/EagerTensor.Creation.cs

@@ -56,7 +56,7 @@ public EagerTensor(Array array, Shape shape) : base(array, shape)
         public EagerTensor(byte[] bytes, Shape shape, TF_DataType dtype) : base(bytes, shape, dtype)
             => NewEagerTensorHandle(_handle);
 
-        void NewEagerTensorHandle(IntPtr h)
+        void NewEagerTensorHandle(SafeTensorHandle h)
         {
             _id = ops.uid();
             _eagerTensorHandle = c_api.TFE_NewTensorHandle(h, tf.Status.Handle);

src/TensorFlowNET.Core/Eager/c_api.eager.cs

@@ -303,7 +303,7 @@ public static void TFE_Execute(SafeOpHandle op, SafeTensorHandleHandle[] retvals
         /// <param name="t">const tensorflow::Tensor&amp;</param>
         /// <returns>TFE_TensorHandle*</returns>
         [DllImport(TensorFlowLibName)]
-        public static extern SafeTensorHandleHandle TFE_NewTensorHandle(IntPtr t, SafeStatusHandle status);
+        public static extern SafeTensorHandleHandle TFE_NewTensorHandle(SafeTensorHandle t, SafeStatusHandle status);
 
         [DllImport(TensorFlowLibName)]
         public static extern SafeTensorHandleHandle TFE_EagerTensorHandle(IntPtr t);
@@ -334,7 +334,7 @@ public static void TFE_Execute(SafeOpHandle op, SafeTensorHandleHandle[] retvals
         /// <param name="status">TF_Status*</param>
         /// <returns></returns>
         [DllImport(TensorFlowLibName)]
-        public static extern IntPtr TFE_TensorHandleResolve(SafeTensorHandleHandle h, SafeStatusHandle status);
+        public static extern SafeTensorHandle TFE_TensorHandleResolve(SafeTensorHandleHandle h, SafeStatusHandle status);
 
 
         /// <summary>

src/TensorFlowNET.Core/NumPy/NDArray.Implicit.cs

@@ -46,11 +46,5 @@ public static implicit operator NDArray(float value)
 
         public static implicit operator NDArray(double value)
             => new NDArray(value);
-
-        public static implicit operator Tensor(NDArray nd)
-            => nd?._tensor;
-
-        public static implicit operator NDArray(Tensor tensor)
-            => new NDArray(tensor);
     }
 }

src/TensorFlowNET.Core/NumPy/NDArray.Index.cs

@@ -8,16 +8,16 @@ namespace Tensorflow.NumPy
 {
     public partial class NDArray
     {
-        public NDArray this[params int[] index]
+        public NDArray this[params int[] indices]
         {
-            get => GetData(index.Select(x => new Slice
+            get => GetData(indices.Select(x => new Slice
             {
                 Start = x,
                 Stop = x + 1,
                 IsIndex = true
             }));
 
-            set => SetData(index.Select(x => 
+            set => SetData(indices.Select(x => 
             {
                 if(x < 0)
                     x = (int)dims[0] + x;
@@ -57,12 +57,37 @@ public NDArray this[NDArray mask]
 
         NDArray GetData(IEnumerable<Slice> slices)
         {
-            var tensor = _tensor[slices.ToArray()];
-            return new NDArray(tensor);
+            if (shape.IsScalar)
+                return GetScalar();
+
+            var tensor = base[slices.ToArray()];
+            if (tensor.Handle == null)
+                tensor = tf.defaultSession.eval(tensor);
+            return new NDArray(tensor.Handle);
+        }
+
+        unsafe T GetAtIndex<T>(params int[] indices) where T : unmanaged
+        {
+            var offset = (ulong)ShapeHelper.GetOffset(shape, indices);
+            return *((T*)data + offset);
+        }
+
+        NDArray GetScalar()
+        {
+            var array = new NDArray(Shape.Scalar, dtype: dtype);
+            unsafe
+            {
+                var src = (byte*)data + dtypesize;
+                System.Buffer.MemoryCopy(src, array.buffer.ToPointer(), bytesize, bytesize);
+            }
+            return array;
         }
 
         NDArray GetData(int[] indices, int axis = 0)
         {
+            if (shape.IsScalar)
+                return GetScalar();
+
             if(axis == 0)
             {
                 var dims = shape.as_int_list();