fix make_tensor_proto when dtype is different.

src/TensorFlowNET.Core/Numpy/Shape.cs

@@ -245,7 +245,7 @@ namespace Tensorflow
                 -1 => "<unknown>",
                 0 => "()",
                 1 => $"({dims[0]},)",
-                _ => $"{string.Join(", ", _dims).Replace("-1", "None")}"
+                _ => $"({string.Join(", ", _dims).Replace("-1", "None")})"
             };
     }
 }

src/TensorFlowNET.Core/Tensors/tensor_util.cs

@@ -110,7 +110,21 @@ namespace Tensorflow
             if (values is TensorProto tp)
                 return tp;
 
-            dtype = values.GetDataType();
+            var origin_dtype = values.GetDataType();
+            if (dtype == TF_DataType.DtInvalid)
+                dtype = origin_dtype;
+            else if(origin_dtype != dtype)
+            {
+                var new_system_dtype = dtype.as_system_dtype();
+                if (values is long[] long_values)
+                {
+                    if (dtype == TF_DataType.TF_INT32)
+                        values = long_values.Select(x => (int)Convert.ChangeType(x, new_system_dtype)).ToArray();
+                }
+                else
+                    values = Convert.ChangeType(values, new_system_dtype);
+            }
+
             shape = shape ?? values.GetShape();
             var tensor_proto = new TensorProto
             {

src/TensorFlowNET.Core/ops.cs

@@ -123,6 +123,9 @@ namespace Tensorflow
             if (dtype == TF_DataType.DtInvalid)
                 dtype = preferred_dtype;
 
+            if (dtype == TF_DataType.DtInvalid)
+                dtype = value.GetDataType();
+
             if (value is EagerTensor eager_tensor && !eager_tensor.IsCreatedInGraphMode)
             {
                 if (tf.executing_eagerly())
@@ -173,8 +176,7 @@ namespace Tensorflow
             if (dtype == TF_DataType.TF_STRING)
                 return ret;
 
-            var original_dtype = value.GetDataType();
-            if (dtype != TF_DataType.DtInvalid && dtype != original_dtype)
+            if (dtype != ret.dtype)
                 ret = gen_math_ops.cast(ret, dtype.as_base_dtype(), name: name);
 
             return ret;