TensorFlow is a computational framework created by Google and has become one of the most diffused deep-learning toolkits. It can work with both CPUs and GPUs and already implements most of the operations and structures required to build and train a complex model. TensorFlow can be installed as a Python package on Linux, Mac, and Windows (with or without GPU support); however, I suggest you follow the instructions provided on the website (the link can be found in the infobox at the end of this chapter) to avoid common mistakes.
The main concept behind TensorFlow is the computational graph, or a set of subsequent operations that transform an input batch into the desired output. In the following figure, there's a schematic representation of a graph:
Starting from the bottom, we have two input nodes (a and b), a transpose operation (that works...