Theano is somewhat similar to a compiler but with the added bonuses of being able to express, manipulate, and optimize mathematical expressions as well as run code on CPU and GPU. Since 2010, Theano has improved release after release and has been adopted by several other Python projects as a way to automatically generate efficient computational models on the fly.
In Theano, you first define the function you want to run by specifying variables and transformation using a pure Python API. This specification will then be compiled to machine code for execution.
As a first example, let's examine how to implement a function that computes the square of a number. The input will be represented by a scalar variable, a, and ...