# [texhax] Problems with pxfonts/txfonts and lambda/Lambda + local macro modes

Johan Glimming glimming at kth.se
Sun Apr 10 16:45:29 CEST 2005

Dear TeXhax,

I have two different questions, so I decided to write them up in one
single email.

1. I have had a hard time to typeset \lambda, \Lambda,
and have still not figured out how to typeset
\forall and \exists *nicely* while using pxfonts
and txfonts. I use these fonts because in my
opinion they look better on slides. However, I am
using \mathtt{} for variables etc, and it looks
extremely ugly with the tx/pxfonts math symbols.

So, I introduced some hacks:

\DeclareSymbolFont{greekletters}  {OML}{cmr}{m}{n}
\DeclareSymbolFont{operators}     {OT1}{cmr}{m}{n}
\DeclareMathSymbol{\lambda}{\mathalpha}
{greekletters}{"15}

And then to write a nice lambda in mathtt{...}-
contexts:

\newcommand{\lam}[2]{\text{${\fontfamily{cmmii} \lambda}$}\tm{#1.\, #2}}

Admittedly, this is an ugly hack, and my question
-finally- is: can I more nicely change greek
letters, and forall/exists to their standard
mathtt format while using pxfonts/txfonts?

2. Suppose I have a bunch of local definitions in LaTeX, and wish to
temporarilly
override some built-in macros, and set, say,
\def\G{\Gamma}
\def\L{\lambda}
\def\D{\Delta}
for convenience. Is there a way to make a
"lambda mode" such that I can write
\lambdaMode
\endLambdaMode
rather than introducing brackets {...} which tends
to be cumbersome to match, and sometimes causes
hard-to-track-down errors in LaTeX?

Yours Sincerely,
Johan Glimming