QcholUtDU               'UtDU' decomposition of a rational matrix
Qdet                    Determinant of a rational matrix
Qinverse                Inverse of a rational matrix
QisInjective            Check injectivity
QisInvertible           Check invertibility
QisSurjective           Check surjectivity
Qkernel                 Kernel of a rational matrix
Qrange                  Range of a rational matrix
Qrank                   Rank of a rational matrix
