\cdbalgorithm{reduce}{}

{\bf NOT YET FUNCTIONAL}
\bigskip

Reduce a sum of tensor monomials of the same type, taking into account
mono-term as well as multi-term symmetries. This does not aim for a
canonical form, but rather for a form in which no monomials occur
which can be expressed (using mono- and multi-term symmetries) as a
linear combination of other monomials appearing in the sum. An example
makes this more clear:
\begin{screen}{0,1}
{m,n,p,q}::Indices(vector).
{m,n,p,q}::Integer(0..10).
R_{m n p q}::RiemannTensor.

R_{m n q p} R_{m n p q} + R_{m p n q} R_{m n p q};
@reduce!(%);
\end{screen}
~
