[NTG-context] Changing font for math function

[Aditya Mahajan]

On Sun, 10 May 2015, Hans Hagen wrote:

> next beta: when one of the stylealternatives text mode else mathmode 
> (default nothing == mathupright)
>
> \starttext
>
> \setupmathematics[functionstyle=,functioncolor=darkred]
>
> {\ss $\sin x$} {\bf $\sin x$}
>
> \setupmathematics[functionstyle=sansbold,functioncolor=darkblue]
>
> {\ss $\sin x$} {\bf $\sin x$}
>
> \setupmathematics[functionstyle=roman,functioncolor=darkgreen]
>
> {\ss $\sin x$} {\bf $\sin x$}
>
> \stoptext

functionstyle=roman is affected by font switches \bf and \it. It should 
not be affected.

\setupmathematics[functionstyle=roman]
{\it $\sin x$}

This is especially important because typically theorems, etc are typeset 
in italic. It tried setting functionstyle=\normalrm but that turns 
everything into italic.

Complete example:


\starttext
\setupmathematics[functionstyle=,functioncolor=darkred]

{\ss $\sin x$} {\bf $\sin x$} {\it $\sin x$}

\setupmathematics[functionstyle=sansbold,functioncolor=darkblue]

{\ss $\sin x$} {\bf $\sin x$} {\it $\sin x$}

\setupmathematics[functionstyle=serif,functioncolor=darkgreen]

{\ss $\sin x$} {\bf $\sin x$} {\it $\sin x$}

\stoptext

Aditya