diff --git a/src/TensorFlowNET.Core/Gradients/math_grad.py.cs b/src/TensorFlowNET.Core/Gradients/math_grad.py.cs
index e72c662d..9713e021 100644
--- a/src/TensorFlowNET.Core/Gradients/math_grad.py.cs
+++ b/src/TensorFlowNET.Core/Gradients/math_grad.py.cs
@@ -72,10 +72,7 @@ namespace Tensorflow
 
         public static bool _ShapesFullySpecifiedAndEqual(Tensor x, Tensor y, Tensor grad)
         {
-            if (x.NDims == 0 && y.NDims == 0 && grad.NDims == 0) return true;
-
-            return string.Join(",", x.shape).Equals(string.Join(",", y.shape)) &&
-                   string.Join(",", x.shape).Equals(string.Join(",", grad.shape));
+            return x.NDims == y.NDims && y.NDims == grad.NDims && x.NDims > -1;
         }
 
         public static (Tensor, Tensor) _SumGrad(Operation op, Tensor grad)
@@ -110,14 +107,15 @@ namespace Tensorflow
             x = math_ops.conj(x);
             y = math_ops.conj(y);
 
-            var realdiv1 = gen_math_ops.real_div(grad, y);
-            var reduce_sum1 = math_ops.reduce_sum(realdiv1, rx);
-            var realdiv2 = gen_math_ops.real_div(-x, y);
-            var realdiv3 = gen_math_ops.real_div(realdiv2, y);
-            var mul = grad * realdiv3;
-            var reduce_sum2 = math_ops.reduce_sum(mul, ry);
+            var realdiv1 = gen_math_ops.real_div(-x, y);
+            var realdiv2 = gen_math_ops.real_div(realdiv1, y);
+            var reduce_sum1 = math_ops.reduce_sum(grad * realdiv2, ry);
+            var reshape1 = gen_array_ops.reshape(reduce_sum1, sy);
+            var realdiv3 = gen_math_ops.real_div(grad, y);
+            var reduce_sum2 = math_ops.reduce_sum(realdiv3, rx);
+            var reshape2 = gen_array_ops.reshape(reduce_sum2, sx);
 
-            return (gen_array_ops.reshape(reduce_sum1, sx), gen_array_ops.reshape(reduce_sum2, sy));
+            return (reshape2, reshape1);
         }
 
         public static (Tensor, Tensor) _PowGrad(Operation op, Tensor grad)
@@ -135,17 +133,16 @@ namespace Tensorflow
             var gx = gen_array_ops.reshape(math_ops.reduce_sum(grad * y * gen_math_ops.pow(x, y - 1.0), rx), sx);
             Tensor log_x = null;
             // Avoid false singularity at x = 0
+            Tensor mask = null;
             if (x.dtype.is_complex())
-            {
                 throw new NotImplementedException("x.dtype.is_complex()");
-            }
             else
-            {
-                var x1 = gen_array_ops.log(x);
-                var y1 = array_ops.zeros_like(x);
-                log_x = array_ops.where(x > 0.0, x1, y1);
-            }
-
+                mask = x > 0.0f;
+            var ones = array_ops.ones_like(x);
+            var safe_x = array_ops.where(mask, x, ones);
+            var x1 = gen_array_ops.log(safe_x);
+            var y1 = array_ops.zeros_like(x);
+            log_x = array_ops.where(mask, x1, y1);
             var gy = gen_array_ops.reshape(math_ops.reduce_sum(grad * z * log_x, ry), sy);
 
             return (gx, gy);
diff --git a/src/TensorFlowNET.Core/Graphs/Graph.cs b/src/TensorFlowNET.Core/Graphs/Graph.cs
index f85f4eff..fcec483e 100644
--- a/src/TensorFlowNET.Core/Graphs/Graph.cs
+++ b/src/TensorFlowNET.Core/Graphs/Graph.cs
@@ -357,6 +357,13 @@ namespace Tensorflow
             return _collections.ContainsKey(name) ? _collections[name] : null;
         }
 
+        public object get_collection_ref(string name)
+        {
+            if (!_collections.ContainsKey(name))
+                _collections[name] = new List<object>();
+            return _collections[name];
+        }
+
         public void Dispose()
         {
             c_api.TF_DeleteGraph(_handle);
diff --git a/src/TensorFlowNET.Core/Operations/array_ops.py.cs b/src/TensorFlowNET.Core/Operations/array_ops.py.cs
index 5bfd279c..8a56ef88 100644
--- a/src/TensorFlowNET.Core/Operations/array_ops.py.cs
+++ b/src/TensorFlowNET.Core/Operations/array_ops.py.cs
@@ -55,6 +55,43 @@ namespace Tensorflow
             return math_ops.rank_internal(input, name, optimize: true);
         }
 
+        /// <summary>
+        /// Creates a tensor with all elements set to 1.
+        /// </summary>
+        /// <param name="tensor"></param>
+        /// <param name="dtype"></param>
+        /// <param name="name"></param>
+        /// <param name="optimize"></param>
+        /// <returns></returns>
+        public static Tensor ones_like<T>(T tensor, TF_DataType dtype = TF_DataType.DtInvalid, string name = "", bool optimize = true)
+            => ones_like_impl(tensor, dtype, name, optimize);
+
+        private static Tensor ones_like_impl<T>(T tensor, TF_DataType dtype, string name, bool optimize = true)
+        {
+            return Python.with<ops.name_scope, Tensor>(new ops.name_scope(name, "ones_like", new { tensor }), scope =>
+            {
+                name = scope;
+                var tensor1 = ops.convert_to_tensor(tensor, name: "tensor");
+                var ones_shape = shape_internal(tensor1, optimize: optimize);
+                if (dtype == TF_DataType.DtInvalid)
+                    dtype = tensor1.dtype;
+                var ret = ones(ones_shape, dtype: dtype, name: name);
+                ret.shape = tensor1.shape;
+                return ret;
+            });
+        }
+
+        public static Tensor ones(Tensor shape, TF_DataType dtype = TF_DataType.TF_FLOAT, string name = "")
+        {
+            dtype = dtype.as_base_dtype();
+            return Python.with<ops.name_scope, Tensor>(new ops.name_scope(name, "ones", new { shape }), scope =>
+            {
+                name = scope;
+                var output = gen_array_ops.fill(shape, constant_op.constant(1.0f, dtype: dtype), name: name);
+                return output;
+            });
+        }
+
         public static Tensor where(Tensor condition, Tensor x = null, Tensor y = null, string name = "")
         {
             if( x == null && y == null)
diff --git a/src/TensorFlowNET.Core/Operations/math_ops.py.cs b/src/TensorFlowNET.Core/Operations/math_ops.py.cs
index ed0a5609..c7bb52c4 100644
--- a/src/TensorFlowNET.Core/Operations/math_ops.py.cs
+++ b/src/TensorFlowNET.Core/Operations/math_ops.py.cs
@@ -111,7 +111,7 @@ namespace Tensorflow
             if (delta == null)
                 delta = 1;
 
-            return Python.with<ops.name_scope, Tensor>(new ops.name_scope(name, "Range", new object[] { start, limit, delta }), scope =>
+            return with<ops.name_scope, Tensor>(new ops.name_scope(name, "Range", new object[] { start, limit, delta }), scope =>
             {
                 name = scope;
                 var start1 = ops.convert_to_tensor(start, name: "start");
@@ -124,15 +124,15 @@ namespace Tensorflow
 
         public static Tensor floordiv(Tensor x, Tensor y, string name = "")
         {
-            return Python.with<ops.name_scope, Tensor>(new ops.name_scope(name, "floordiv", new object[] { }), scope =>
+            return with<ops.name_scope, Tensor>(new ops.name_scope("", "floordiv", new { x, y }), scope =>
             {
-                return gen_math_ops.floor_div(x, y, name);
+                return gen_math_ops.floor_div(x, y, scope);
             });
         }
 
         public static Tensor rank_internal(Tensor input, string name = "", bool optimize = true)
         {
-            return Python.with<ops.name_scope, Tensor>(new ops.name_scope(name, "Rank", new List<Tensor> { input }), scope =>
+            return with<ops.name_scope, Tensor>(new ops.name_scope(name, "Rank", new List<Tensor> { input }), scope =>
             {
                 name = scope;
                 var input_tensor = ops.convert_to_tensor(input);
diff --git a/src/TensorFlowNET.Core/Tensors/Tensor.Creation.cs b/src/TensorFlowNET.Core/Tensors/Tensor.Creation.cs
index 73713d36..d31ec927 100644
--- a/src/TensorFlowNET.Core/Tensors/Tensor.Creation.cs
+++ b/src/TensorFlowNET.Core/Tensors/Tensor.Creation.cs
@@ -63,31 +63,6 @@ namespace Tensorflow
                     break;
                 case "Single":
                     Marshal.Copy(nd1.Data<float>(), 0, dotHandle, nd.size);
-                    /*if (nd.size > 1)
-                    {
-                        var bb = nd.Data<byte>();
-                        var bytes = Marshal.AllocHGlobal(bb.Length);
-                        Marshal.Copy(bb, 0, bytes, bb.Length);
-                        ulong bytes_len = c_api.TF_StringEncodedSize((ulong)bb.Length);
-                        var dataTypeByte = ToTFDataType(nd.dtype);
-                        // shape
-                        var dims2 = nd.shape.Select(x => (long)x).ToArray();
-
-                        var tfHandle2 = c_api.TF_AllocateTensor(dataTypeByte,
-                            dims2,
-                            nd.ndim,
-                            bytes_len + sizeof(Int64));
-
-                        dotHandle = c_api.TF_TensorData(tfHandle2);
-                        Marshal.WriteInt64(dotHandle, 0);
-                        c_api.TF_StringEncode(bytes, (ulong)bb.Length, dotHandle + sizeof(Int64), bytes_len, status);
-                        return tfHandle2;
-                    }
-                    else
-                    {
-                        Marshal.Copy(nd1.Data<float>(), 0, dotHandle, nd.size);
-                    }*/
-                    
                     break;
                 case "Double":
                     Marshal.Copy(nd1.Data<double>(), 0, dotHandle, nd.size);
diff --git a/src/TensorFlowNET.Core/Tensors/Tensor.Operators.cs b/src/TensorFlowNET.Core/Tensors/Tensor.Operators.cs
index b428deee..cbfa7af6 100644
--- a/src/TensorFlowNET.Core/Tensors/Tensor.Operators.cs
+++ b/src/TensorFlowNET.Core/Tensors/Tensor.Operators.cs
@@ -27,8 +27,10 @@ namespace Tensorflow
         public static Tensor operator %(Tensor x, Tensor y) => BinaryOpWrapper("mod", x, y);
 
         public static Tensor operator >(Tensor x, int y) => gen_array_ops.greater(x, y);
+        public static Tensor operator >(Tensor x, float y) => gen_array_ops.greater(x, y);
         public static Tensor operator >(Tensor x, double y) => gen_array_ops.greater(x, y);
         public static Tensor operator <(Tensor x, int y) => gen_array_ops.less(x, y);
+        public static Tensor operator <(Tensor x, float y) => gen_array_ops.less(x, y);
         public static Tensor operator <(Tensor x, double y) => gen_array_ops.less(x, y);
 
         private static Tensor BinaryOpWrapper<Tx, Ty>(string name, Tx x, Ty y)
diff --git a/src/TensorFlowNET.Core/Tensors/Tensor.cs b/src/TensorFlowNET.Core/Tensors/Tensor.cs
index 50a5bbdd..3d8f9be4 100644
--- a/src/TensorFlowNET.Core/Tensors/Tensor.cs
+++ b/src/TensorFlowNET.Core/Tensors/Tensor.cs
@@ -68,7 +68,12 @@ namespace Tensorflow
                     c_api.TF_GraphSetTensorShape(this.Graph, this._as_tf_output(), value, value.Length, status);
             }
         }
-        
+
+        public int[] _shape_tuple()
+        {
+            return null;
+        }
+
         /// <summary>
         /// number of dimensions
         /// 0	Scalar (magnitude only)
diff --git a/src/TensorFlowNET.Core/Train/GradientDescentOptimizer.cs b/src/TensorFlowNET.Core/Train/GradientDescentOptimizer.cs
index 24f7b5c4..8473d819 100644
--- a/src/TensorFlowNET.Core/Train/GradientDescentOptimizer.cs
+++ b/src/TensorFlowNET.Core/Train/GradientDescentOptimizer.cs
@@ -6,7 +6,7 @@ namespace Tensorflow
 {
     public class GradientDescentOptimizer : Optimizer
     {
-        public GradientDescentOptimizer(double learning_rate, bool use_locking = false, string name = "GradientDescent") 
+        public GradientDescentOptimizer(float learning_rate, bool use_locking = false, string name = "GradientDescent") 
             : base(learning_rate, use_locking, name)
         {
             LearningRate = learning_rate;
diff --git a/src/TensorFlowNET.Core/Train/Optimizer.cs b/src/TensorFlowNET.Core/Train/Optimizer.cs
index 508d220b..7201d989 100644
--- a/src/TensorFlowNET.Core/Train/Optimizer.cs
+++ b/src/TensorFlowNET.Core/Train/Optimizer.cs
@@ -20,14 +20,14 @@ namespace Tensorflow
         public static int GATE_GRAPH = 2;
 
         public string Name { get; set; }
-        public double LearningRate { get; set; }
+        public float LearningRate { get; set; }
         public Tensor LearningRateTensor { get; set; }
         public bool _use_locking;
         public Dictionary<string, object> _slots;
         public Dictionary<string, object> _non_slot_dict;
         public Dictionary<string, object> _deferred_slot_restorations;
 
-        public Optimizer(double learning_rate, bool use_locking, string name = "")
+        public Optimizer(float learning_rate, bool use_locking, string name = "")
         {
             if (String.IsNullOrEmpty(name))
                 throw new NotImplementedException("Must specify the optimizer name");
@@ -114,6 +114,13 @@ namespace Tensorflow
 
                 }
 
+                if (!tf.context.executing_eagerly())
+                {
+                    var train_op = ops.get_collection_ref(ops.GraphKeys.TRAIN_OP) as List<object>;
+                    if (!train_op.Contains(apply_updates))
+                        train_op.Add(apply_updates);
+                }
+
                 return apply_updates;
             });
         }
diff --git a/src/TensorFlowNET.Core/Train/tf.optimizers.cs b/src/TensorFlowNET.Core/Train/tf.optimizers.cs
index e82d3dc0..99fbb74a 100644
--- a/src/TensorFlowNET.Core/Train/tf.optimizers.cs
+++ b/src/TensorFlowNET.Core/Train/tf.optimizers.cs
@@ -9,7 +9,7 @@ namespace Tensorflow
     {
         public static class train
         {
-            public static Optimizer GradientDescentOptimizer(double learning_rate) => new GradientDescentOptimizer(learning_rate);
+            public static Optimizer GradientDescentOptimizer(float learning_rate) => new GradientDescentOptimizer(learning_rate);
 
             public static Saver Saver() => new Saver();
 
diff --git a/src/TensorFlowNET.Core/ops.GraphKeys.cs b/src/TensorFlowNET.Core/ops.GraphKeys.cs
index d828820a..9c6c76e3 100644
--- a/src/TensorFlowNET.Core/ops.GraphKeys.cs
+++ b/src/TensorFlowNET.Core/ops.GraphKeys.cs
@@ -33,6 +33,8 @@ namespace Tensorflow
             /// </summary>
             public static string GLOBAL_VARIABLES = "variables";
 
+            public static string TRAIN_OP = "train_op";
+
             public static string[] _VARIABLE_COLLECTIONS = new string[] { "variables", "trainable_variables" }; 
             /// <summary>
             /// Key to collect BaseSaverBuilder.SaveableObject instances for checkpointing.
diff --git a/src/TensorFlowNET.Core/ops.py.cs b/src/TensorFlowNET.Core/ops.py.cs
index 2bbe0537..346fe8bc 100644
--- a/src/TensorFlowNET.Core/ops.py.cs
+++ b/src/TensorFlowNET.Core/ops.py.cs
@@ -45,6 +45,11 @@ namespace Tensorflow
             return get_default_graph().get_collection(key, scope);
         }
 
+        public static object get_collection_ref(string key)
+        {
+            return get_default_graph().get_collection_ref(key);
+        }
+
         private static Graph default_graph;
         public static Graph get_default_graph()
         {
diff --git a/test/TensorFlowNET.Examples/LinearRegression.cs b/test/TensorFlowNET.Examples/LinearRegression.cs
index 4008bd72..48713be9 100644
--- a/test/TensorFlowNET.Examples/LinearRegression.cs
+++ b/test/TensorFlowNET.Examples/LinearRegression.cs
@@ -21,7 +21,7 @@ namespace TensorFlowNET.Examples
             // Parameters
             float learning_rate = 0.01f;
             int training_epochs = 1000;
-            int display_step = 1;
+            int display_step = 10;
 
             // Training Data
             var train_X = np.array(3.3f, 4.4f, 5.5f, 6.71f, 6.93f, 4.168f, 9.779f, 6.182f, 7.59f, 2.167f,
@@ -29,9 +29,9 @@ namespace TensorFlowNET.Examples
             var train_Y = np.array(1.7f, 2.76f, 2.09f, 3.19f, 1.694f, 1.573f, 3.366f, 2.596f, 2.53f, 1.221f,
                          2.827f, 3.465f, 1.65f, 2.904f, 2.42f, 2.94f, 1.3f);
             var n_samples = train_X.shape[0];
-            
+
             // tf Graph Input
-            var X = tf.placeholder(tf.float32);
+            /*var X = tf.placeholder(tf.float32);
             var Y = tf.placeholder(tf.float32);
 
             // Set model weights 
@@ -55,7 +55,14 @@ namespace TensorFlowNET.Examples
             // radient descent
             // Note, minimize() knows to modify W and b because Variable objects are trainable=True by default
             var grad = tf.train.GradientDescentOptimizer(learning_rate);
-            var optimizer = grad.minimize(cost);
+            var optimizer = grad.minimize(cost);*/
+
+            var new_saver = tf.train.import_meta_graph("save_model.meta", import_scope: "import");
+
+            var X = graph.OperationByName("Placeholder");
+            var Y = graph.OperationByName("Placeholder_1");
+            var W = graph.OperationByName("weight");
+            var optimizer = graph.OperationByName("GradientDescent");
 
             // Initialize the variables (i.e. assign their default value)
             var init = tf.global_variables_initializer();
@@ -71,14 +78,15 @@ namespace TensorFlowNET.Examples
                 {
                     foreach (var (x, y) in zip<float>(train_X, train_Y))
                     {
+                        var w = sess.run(W);
                         sess.run(optimizer,
                             new FeedItem(X, x),
                             new FeedItem(Y, y));
-                        var w = sess.run(W);
+                        w = sess.run(W);
                     }
 
                     // Display logs per epoch step
-                    if ((epoch + 1) % display_step == 0)
+                    /*if ((epoch + 1) % display_step == 0)
                     {
                         var c = sess.run(cost, 
                             new FeedItem(X, train_X),
@@ -86,7 +94,7 @@ namespace TensorFlowNET.Examples
                         var rW = sess.run(W);
                         Console.WriteLine($"Epoch: {epoch + 1} cost={c} " +
                                     $"W={rW} b={sess.run(b)}");
-                    }
+                    }*/
                 }
 
                 Console.WriteLine("Optimization Finished!");