__HEADER__(Faktor package that also handles cofaktors)

% Extension the faktor package for 
% - cofaktor command that provides A \ B notation
% - scaling the / in the middle
% - fine positioning of enumerator / denominator

% This is essentially taken from the stackexchange question found at
% https://tex.stackexchange.com/questions/27591/extending-the-faktor-package
% and answered by 'Werner' (https://tex.stackexchange.com/users/5764/werner)
%
% This package only packages the corresponding answer and provides an analoguous way of a \cofactor command

%Dependencies
\RequirePackage{xparse}
\RequirePackage{amssymb} % provides \diagup and \diagdown
\RequirePackage{ifthen} % ifthenelse syntax
\RequirePackage{mathtools}


\DeclareDocumentCommand{\faktor}{s m O{0.5} m O{-0.5}}{% \newfaktor[*]{#2}[#3]{#4}[#5] -> #2/#4
  \setbox0=\hbox{\ensuremath{#2}}% Store numerator
  \setbox1=\hbox{\ensuremath{\diagup}}% Store slash /
  \setbox2=\hbox{\ensuremath{#4}}% Store denominator
  \raisebox{#3\ht1}{\usebox0}% Numerator
  \mkern-5mu\ifthenelse{\equal{#1}{\BooleanTrue}}% Slash /
    {\diagup}% regular \faktor slash
    {\rotatebox{-44}{\rule[#5\ht2]{0.4pt}{-#5\ht2+#3\ht0+\ht0}}}% tilted rule as a slash
  \mkern-4mu%
  \raisebox{#5\ht2}{\usebox2}% Denominator
}

\DeclareDocumentCommand{\cofaktor}{s m O{-0.5} m O{0.5}}{% \newfaktor[*]{#2}[#3]{#4}[#5] -> #2/#4
  \setbox0=\hbox{\ensuremath{#2}}% Store numerator
  \setbox1=\hbox{\ensuremath{\diagdown}}% Store slash /
  \setbox2=\hbox{\ensuremath{#4}}% Store denominator
  \raisebox{#3\ht1}{\usebox0}% Numerator
  \mkern-5mu\ifthenelse{\equal{#1}{\BooleanTrue}}% Slash /
    {\diagdown}% regular \faktor slash
    {\rotatebox{44}{\rule[-#5\ht2]{0.4pt}{#5\ht2-#3\ht0+\ht0}}}% tilted rule as a slash
  \mkern-4mu%
  \raisebox{#5\ht2}{\usebox2}% Denominator
}