my model contains lstm with batch. model is so simple, But after running some batches not even completed one epoch the model parameters are becoming nan. I tried with learning rate as 0.0 even though they are becoming zero. may i know why? My code is at https://bitbucket.org/Vsbiradar/siamese-network/src/b5d6428c045cdcc1900fa216bece08d0012dab9b/siamese-network/siamese.py?at=master&fileviewer=file-view-default 20