General ⇒ subscripts with mbox

[daviddoria]

when I do something like this

Code: Select all

r_\mbox{12}

To indicate the 1st row, 2nd column entry of a matrix, the subscripts are way bigger than they should be. Is this not how I'm supposed to do non-italicized subscripts?

Thanks,
Dave

[gmedina]

Hi,

the \text command provided by the amsmath package could be useful. Please compare the results obtained in the following example:

Code: Select all

\documentclass{article}
\usepackage{amsmath}

\begin{document}

$r_{ab}$

$r_{\text{ab}}$

$r_{\mbox{ab}}$

\end{document}

[daviddoria]

beautiful

[daleif]

Do NOT use \text for wordlike subscripts!

Code: Select all

\documentclass{memoir}
\usepackage{amsmath}
\begin{document}
\[
   blah_{\text{test}}
\]
\itshape not italic text
\[
   blah_{\text{test}}
\]
still italic, but this is the right way:
\[
   blah_{\textup{test}}
\]
\end{document}

many people make this mistake. \textup is also better than \textrm as \textrm would disable sans-serif if it was present, \textup just disables italics (and of course changes to the text font)