🚀 go-pugleaf

I am trying to modify the equation labels by redefining the "\theequation"
command, see the attached sample tex file. But it works only in the "equation"
environment, not in the "eqnarray" environment. 

Any suggestions? 

Thank you.

Herong Yang
herong@twinkie.cc.mcgill.ca
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\documentstyle{report}
\begin{document}
......
\appendix
\chapter{Reference}
\begin{eqnarray}
\renewcommand{\theequation}{\Alph{chapter}.\alph{equation}}
    x + y + z & = & a + b + c \\
        x + y & = & b + c     \\
            x & = & c         \\
\end{eqnarray}
\begin{equation}
\renewcommand{\theequation}{\Alph{chapter}.\alph{equation}}
 f_s' = { {\partial f} \over {\partial x} }
        { {\partial x} \over {\partial s} }
      + { {\partial f} \over {\partial y} }
        { {\partial y} \over {\partial s} }
\end{equation}
\end{document}