beamercomputer-modernfontsmath-modexetex
I am writing a presentation using the beamer class and XeTeX. I have changed the sans font using \setsansfont. Now some symbols in my equations are rendered using the mono font (like the lowercase letters).
How can I force math mode to render all symbols in the equations in the default Computer Modern, ignoring the font set with \setsansfont?
The following example using \mathrm seems to work nicely in MikTeX 2.9 with a tikz-box:
\documentclass{article}
\usepackage{lipsum}
\usepackage{tikz}
\newcommand*{\mycolorbox}[1]{
\begin{tikzpicture}
\node[rectangle,inner xsep=10pt,inner ysep=10pt,
anchor=south,text width=\columnwidth,shade]{#1};
\end{tikzpicture}
}
\renewcommand{\familydefault}{\sfdefault}
\usepackage{helvet}
\usepackage[mathrmOrig]{sfmath}
\begin{document}
sans serif text
\mycolorbox{Sans serif: $a + b$, CM: {$\mathrm{c}$}}
\end{document}
I think you need to explicitly enable this with the mathrmOrig option in sfmath. The result looks like this:
You could load the cfr-lm package, i.e., write \usepackage{cfr-lm} in the preamble. If the package is loaded in this way, old-style numerals will be used in text mode and lining numerals will be used in math mode. Latin Modern is a clone of Computer Modern; the basic glyphs (those in the ASCII set) are essentially indistinguishable from Computer Modern; you'll notice big improvements in some glyphs with accents and diacritics when using Latin Modern.
To get lining numbers, use either math mode or the package's \textl macro.
\documentclass{article}
\usepackage{cfr-lm}
\begin{document}
\obeylines % just for this example
\textl{0123456789}
$0123456789$
0123456789
\textbf{0123456789}
\textit{0123456789}
\textbf{\textit{0123456789}}
\textsf{0123456789}
\texttt{0123456789}
\end{document}
Best Answer
By default, Beamer does some math font manipulation, because many fonts, such as the cm-sans used by default, don't provide matching mathematical glyphs. If you want the standard Computer Modern (serif) math font, just say
in the preamble. This suppresses any auto-manipulations.