Optimizer init with parameters, test=develop (#4154)

* Optimizer init with parameters, test=develop

* fix bug for eval, test=develop

dygraph/ptb_lm/ptb_dy.py

@@ -323,7 +323,7 @@ def train_ptb_lm():
             lr_arr.append(new_lr)
 
         sgd = SGDOptimizer(learning_rate=fluid.layers.piecewise_decay(
-            boundaries=bd, values=lr_arr))
+            boundaries=bd, values=lr_arr), parameter_list=ptb_model.parameters())
 
         def eval(model, data):
             print("begion to eval")
@@ -338,8 +338,8 @@ def train_ptb_lm():
             train_data_iter = reader.get_data_iter(data, batch_size, num_steps)
             for batch_id, batch in enumerate(train_data_iter):
                 x_data, y_data = batch
-                x_data = x_data.reshape((-1, num_steps))
-                y_data = y_data.reshape((-1, 1))
+                x_data = x_data.reshape((-1, num_steps, 1))
+                y_data = y_data.reshape((-1, num_steps, 1))
                 x = to_variable(x_data)
                 y = to_variable(y_data)
                 init_hidden = to_variable(init_hidden_data)