wafoon

How to slove this problem(LookupError: No gradient defined for operation 'pool_5' (op type: RoiPool))

2

/home/fermion/anaconda3/lib/python3.5/site-packages/tensorflow/python/ops/gradients_impl.py:93: UserWarning: Converting sparse IndexedSlices to a dense Tensor of unknown shape. This may consume a large amount of memory. "Converting sparse IndexedSlices to a dense Tensor of unknown shape....