The Logistic Regression accuracy is correct. But still has performance issue.

src/TensorFlowHub/MnistDataSet.cs

@@ -20,7 +20,7 @@ namespace Tensorflow.Hub
             NumOfExamples = images.shape[0];
 
             images = images.reshape(images.shape[0], images.shape[1] * images.shape[2]);
-            images.astype(dataType);
+            images = images.astype(dataType);
             images = np.multiply(images, 1.0f / 255.0f);
             Data = images;
 

src/TensorFlowHub/Utils.cs

@@ -116,11 +116,11 @@ namespace Tensorflow.Hub
         {
             var cols = 0;
 
-            await Task.Delay(1000);
+            await Task.Delay(100);
 
             while (!cts.IsCancellationRequested)
             {
-                await Task.Delay(1000);
+                await Task.Delay(100);
                 Console.Write(".");
                 cols++;
 

src/TensorFlowNET.Core/Tensors/Tensor.Creation.cs

@@ -514,7 +514,7 @@ namespace Tensorflow
             if (nd.dtype.Name != "String")
             {
                 buffersize = (nd.size * nd.dtypesize);
-                dotHandle = Marshal.AllocHGlobal(buffersize);
+                // dotHandle = Marshal.AllocHGlobal(buffersize);
             }
 
             var dataType = ToTFDataType(nd.dtype);