Ensuring math mode

\ensuremath {<math commands>}

In L^ATEX 2.09, if you wanted a command to work both in math mode and in text mode, the suggested method was to define something like:

   \newcommand{\Gp}{\mbox{$G_p$}}

Unfortunately, the \mbox stops \Gp changing size correctly in (for instance) subscripts or a fraction. In L^ATEX2_e you can define it thus:

   \newcommand{\Gp}{\ensuremath{G_p}}

Now \Gp will work correctly in all contexts. This is because the \ensuremath does nothing, producing simply G_p, when \Gp is used within math mode; but it ensures that math mode is entered (and exited) as required when \Gp is used in text mode.