How to calculate precision and recall in Keras

Question

I am building a multi-class classifier with Keras 2.02 (with Tensorflow backend)，and I do not know how to calculate precision and recall in Keras. Please help me.

Answer 1

As of Keras 2.0, precision and recall were removed from the master branch. You will have to implement them yourself. Follow this guide to create custom metrics : Here.

Precision and recall equation can be found Here

Or reuse the code from keras before it was removed Here.

There metrics were remove because they were batch-wise so the value may or may not be correct.