Gradient for log
@RegisterGradient("log")
def _log_gradient(op, grad):
"""Computes the gradients for `log`.
Args:
op: The `log` `Operation` that we are differentiating
grad: Gradient with respect to the output of the `log` op.
Returns:
Gradients with respect to the input of `log`.
"""
x = op.inputs[0]
return grad/x
