% This is apeqnum.sty
% 8-November-1990
% Don Hosek
% Style option for article.sty and derivatives; causes equations
% to be numbered A1, A2, A3, B1, etc. in a document.
% First save a copy of the old meaning of \appendix
\let\apeqnum@appendix=\appendix
% Now, we will redefine \appendix so that it does the following:
% (1) The old functions of \appendix (\apeqnum@appendix)
% (2) Causes equations to be numbered beginning from one at
% the beginning of each appendix (this is accomplished
% for the article style with the command
% \@addtoreset{equation}{section})
% (3) Change the definition of \theequation (which prints the
% equation numbers) so that the appendix letter is prepended.
\def\appendix{%
\apeqnum@appendix % (1)
\@addtoreset{equation}{section} % (2)
\def\theequation{\thesection\arabic{equation}}} % (3)