Run error with your code

[Xls1994]

Hi, when I use you code in Keras 2.0.1. It seems wrong with the dot function.
I got the ValueError:
Shape must be rank 2 but is rank 3 for 'dot_1/MatMul' (op: 'MatMul') with input shapes: [?,50], [?,50,300].
Have you ever met this problem?
Thanks