% $Date: 2003/09/15 16:37:46 $ $Author: nthiery $ $Revision: 1.1.1.1 $

\begin{Mhelppage}{IssA}%
  {V. Prosper}%
  \begin{MInfo}
    \eng{tests whether the argument is a generator of the s-basis on a
      formal alphabet expression}
  \end{MInfo}
  

\begin{MCalls}
\Mcall{expr}
\end{MCalls}

\begin{MParameters}
  \param{expr}
  \eng{any expression}
\end{MParameters}

\begin{MIntro}
  \eng{
The {\Mthis} function tests whether \Mex{expr} is a generator of
the s-basis on a formal alphabet expression, that is a Schur
function on a given alphabet.

The indexing vector must be a partition.

The alphabet can be for instance a polynomial in \Mex{A1, A2, ...}.

Note that the \Mex{A}i's are the only formal variables in alphabets.
}
\end{MIntro}

\begin{MExample}{ex1}
\begin{Mexin}
muEC::TYP::IssA( s[](A1-A2) );
\end{Mexin}
\begin{Mexout}
                             TRUE
\end{Mexout}
\begin{Mexin}
muEC::TYP::IssA( s[3,3,1](k/3*A3) );
\end{Mexin}
\begin{Mexout}
                             TRUE
\end{Mexout}
\end{MExample}

\MRelatedFunctions{IseA,IshA,IsmA,IspA,SfA,Iss}
\end{Mhelppage}
