  Cadabra is an open access program ideally suited to complex tensor
commutations in General Relativity. Tensor expressions are written in LaTeX
while an enhanced version of Python is used to control the computations. This
tutorial assumes no prior knowledge of Cadabra. It consists of a series of
examples covering a range of topics from basic syntax such as declarations,
functions, program control, component computations, input and output through to
complete computations including a derivation of two of the BSSN equations from
the ADM equations. Numerous exercises are included along with complete
solutions. All of the source code for the examples, exercises and solutions are
available on GitHub.
