## 前后传播采用不同方式

How Can I Define Only the Gradient for a Tensorflow Subgraph?

Suppose you want group of ops that behave as f(x) in forward mode, but as g(x) in the backward mode. You implement it as

## 停止部分变量的梯度计算

How to stop gradient for some entry of a tensor in tensorflow提供了一个较好的方法：