## decompose

Decompose a tensor monomial on a given basis of monomials.

The basis
should be given in the second argument. All tensor symmetries,
including those implied by Young tableau Garnir symmetries, are taken
into account. Example,{m,n,p,q}::Indices(vector).
{m,n,p,q}::Integer(0..10).
R_{m n p q}::RiemannTensor.
ex:=R_{m n q p} R_{m p n q};

\(\displaystyle{}R_{m n q p} R_{m p n q}\)

R_{m n q p} R_{m p n q}

decompose(ex, $R_{m n p q} R_{m n p q}$);

\(\displaystyle{}\left[ - \frac{1}{2}\right]\)

{ - 1/2 }

Note that this algorithm does not yet take into account
dimension-dependent identities, but it is nevertheless already
required that the index range is specified.