Function: qfisominit
Section: linear_algebra
C-Name: qfisominit0
Prototype: GDGDG
Help: qfisominit(G,{fl},{m}): G being a square and symmetric matrix representing an
integral positive definite quadratic form, this function returns a structure
allowing to compute isomorphisms between G and other quadratic form faster.
Doc:
$G$ being a square and symmetric matrix with integer entries representing a
positive definite quadratic form, return an \kbd{isom} structure allowing to
compute isomorphisms between $G$ and other quadratic forms faster.
The interface of this function is experimental and will likely change in future
release.
If present, the optional parameter \var{fl} must be a \typ{VEC} with two
components. It allows to specify the invariants used, which can make the
computation faster or slower. The components are
\item \kbd{fl[1]} Depth of scalar product combination to use.
\item \kbd{fl[2]} Maximum level of Bacher polynomials to use.
If present, $m$ must be the set of vectors of norm up to the maximal of the
diagonal entry of $G$, either as a matrix or as given by \kbd{qfminim}.
Otherwise this function computes the minimal vectors so it become very
lengthy as the dimension of $G$ grows.
Variant: Also available is
\fun{GEN}{qfisominit}{GEN F, GEN fl}
where $F$ is a vector of \kbd{zm}.