upgrade SciSharp.TensorFlow.Redist to 2.1.0.

src/TensorFlowNET.Core/Operations/gen_math_ops.cs

@@ -321,6 +321,14 @@ namespace Tensorflow
 
         public static Tensor tan(Tensor x, string name = null)
         {
+            if (tf.context.executing_eagerly())
+            {
+                var _result = wrap_tfe_src.TFE_FastPathExecute(tf.context, tf.context.device_name,
+                    "Tan", name, null,
+                    x);
+                return _result;
+            }
+
             var _op = _op_def_lib._apply_op_helper("Tan", name, args: new { x });
 
             return _op.outputs[0];

test/TensorFlowNET.UnitTest/Tensorflow.UnitTest.csproj

@@ -34,7 +34,7 @@
     <PackageReference Include="MSTest.TestAdapter" Version="2.1.0" />
     <PackageReference Include="MSTest.TestFramework" Version="2.1.0" />
     <PackageReference Include="NumSharp.Lite" Version="0.1.7" />
-    <PackageReference Include="SciSharp.TensorFlow.Redist" Version="1.15.1" />
+    <PackageReference Include="SciSharp.TensorFlow.Redist" Version="2.1.0" />
   </ItemGroup>
 
   <ItemGroup>

test/TensorFlowNET.UnitTest/math_test/MathOperationTest.cs

@@ -17,10 +17,19 @@ namespace TensorFlowNET.UnitTest.math_test
         [TestMethod]
         public void Sin()
         {
-            var b = tf.sin(a, name: "sin");
+            var b = tf.sin(a, name: "Sin");
             var expected = new float[] { 0.84147096f, -0.47942555f, -0.2555412f, -0.8632094f /*python output -0.86320937*/,  0f, -0.21511999f };
             var actual = b.ToArray<float>();
             Assert.IsTrue(Enumerable.SequenceEqual(expected, actual));
         }
+
+        [TestMethod]
+        public void Tan()
+        {
+            var b = tf.tan(a, name: "Tan");
+            var expected = new float[] { 1.5574077f, -0.5463025f, 0.264317f, 1.709847f, 0f, -0.2202772f };
+            var actual = b.ToArray<float>();
+            Assert.IsTrue(Enumerable.SequenceEqual(expected, actual));
+        }
     }
 }