🚀 go-pugleaf

"Geoff" <megdd@alinga.newcastle.edu.au> writes:

> when I write an equation such as:
> 
> \begin{equation}
> f \frac{\partial f}{\partial \mu} = \frac{\rm{d} f}{\rm{d} \mu}
> \end{equation}
> 
> the f's on the left hand side of the equation are typeset as a script form
> of f (which is what I want), whereas those on the right hand side are roman
> f's even though they are not contained in the \rm{}.

With archaic LaTeX (2.09) the use of \rm, whether in math mode or in
text, is as a switch which controls everything inside the same group
(that is inside the same set of braces) and does _not_ take an
argument.  This is derived from the original plain TeX definition, and
means that on the right hand side everything inside the braces of the
\frac arguments is in roman, not math italic.  Using the out of date
2.09 version the above should read something like:

\begin{equation}
f \frac{\partial f}{\partial \mu} = \frac{{\rm d} f}{{\rm d} \mu}
\end{equation}

With a more recent version of LaTeX (any of the releases of 2e since
1994) you can use the \mathrm commands which _do_ take an argument
(and so seems more consistent with LaTeX usage).  In this case you
could write the above as something like:

\begin{equation}
f \frac{\partial f}{\partial \mu} = \frac{\mathrm{d} f}{\mathrm{d} \mu}
\end{equation}

-- 
Stephen Harker                                        s-harker@adfa.edu.au
School of Physics               Baloney Baffles brains: Eric Frank Russell
University College
UNSW, ADFA