# Use isomath with Helvetica

I'd like to combine Helvetica of the package helvet as main text font and isomath as math font in my custom class. Because isomath is a little bit smaller then Helvetica I'd like to scale it:

However

% ...
\RequirePackage{helvet}
\RequirePackage[scaled=1.2]{isomath}
\RequirePackage[T1]{fontenc}
% ...


doesn't seem to work. I tried to read the docs but don't really understand them. Can someone help?

MWE

\documentclass{scrartcl}

\usepackage{helvet}
\renewcommand\familydefault{\sfdefault}
\usepackage[scaled=0.5]{isomath}
\usepackage[T1]{fontenc}

\begin{document}
\noindent
This is some text with the inline formula $F = m a$. As you may notice the height of the fonts doesn't match. The \texttt{scaled} wont rescale \emph{isomath}.
\end{document}


• Doesn't work in what sense? Please add a MWE. – JPi Mar 30 '17 at 15:42
• Added an MWE using scrartcl – liondog Mar 30 '17 at 15:51

From the documentation of isomath:

To improve the chances of finding a matching sans serif math font, the fonts fav, iwona, jkpss, and llcmss can be scaled with the scaled option (cf. Examples). For other fonts, the option is ignored.

So scaling a) only works for some fonts and b) is for sans serif math fonts, which you are not using.

Instead maybe just do it the other way round and scale down the helvet package:

\documentclass{scrartcl}
\usepackage[T1]{fontenc}

\usepackage[scaled=0.93]{helvet}
\renewcommand\familydefault{\sfdefault}
\usepackage{isomath}

\begin{document}
\noindent
This is some text with the inline formula F$F = m a$. As you may notice the height of the fonts doesn't match. The \texttt{scaled} wont rescale \emph{isomath}.
\end{document}