Theano is a Python library that allows you to define, optimize, and evaluate mathematical expressions involving multi-dimensional arrays efficiently.
Theano features:
* tight integration with numpy - Use numpy.ndarray in Theano-compiled functions.
* transparent use of a GPU - Perform data-intensive calculations up to 140x faster than with CPU.(float32 only)
* symbolic differentiation - Let Theano do your derivatives.
* speed and stability optimizations - Get the right answer for log(1+x) even when x is really tiny.
* dynamic C code generation - Evaluate expressions faster.
* extensive unit-testing and self-verification - Detect and diagnose many types of mistake.

Theano has been powering large-scale computationally intensive scientific investigations since 2007. But it is also approachable enough to be used in the classroom (IFT6266 at the University of Montreal).