# [texhax] math \fontdimen

Donald Arseneau asnd at triumf.ca
Mon Feb 9 09:37:34 CET 2009

Uwe Lück <uwe.lueck at web.de> writes:

> >\xheight = \fontdimen 5 \textfont 2 \relax
>
> Now I wonder a little whether I can be sure that (outside PlainTeX) 2 will be
> the symbols family.

Yes, families 0, 1, 2, and 3 are guaranteed to have the same meaning.
The special math fontdimen parameters from the symbol and extension fonts
are required in the fonts for families 2 and 3 for TeX to typeset math.
See the first page of Appendix G.

--
Donald Arseneau                          asnd at triumf.ca