# Accessing AMS fonts in LaTex

The document amsfndoc.pdf, available from the AMS website , has large tables of unusual fonts at the end. Can someone explain how I can access these fonts in a standard installation of LaTex? I use TexShop, with MacTex.

I've looked around on the web a bit, and I can't find any down-to-earth explanation.

For example, say I wanted to access the unusual curly braces located at positions (3,C) and (3,D) in the last chart on the last page of amsfndoc.pdf. These are apparently part of the Computer Modern math extension font (cmex10). What would I type into my .tex file? Do I need to install extra packages that are not part of standard LaTex installations?

Let me point out that I have no trouble using the fonts on, say, p. 20 of amsfndoc.pdf, since these all have names like \digamma and \varkappa, etc., which I can just type into my .tex file. I'm guessing there is some formula for translating the hexadecimal position in the cmex10 chart into a LaTex command, but I don't know what that formula is...

-
Those are not curly braces, but parts of the extensible usually braces (which are build from pieces) –  Mariano Suárez-Alvarez Apr 29 '10 at 20:01
Basically you can find the vast majority of symbols and their codes, along with the packages to include here: ctan.org/tex-archive/info/symbols/comprehensive/symbols-a4.pdf. Some of the symbols require \usepackage{amssymb}, but it's all outlined in the doc. –  Jason Polak Apr 29 '10 at 20:11
Mariano is right, of course, which explains why there are no user defined macros for accessing those characters. If you need direct access to some glyph in the current font, there is the builtin TeX primitive \mathchar for doing that. Knuth's TeX book is the appropriate place to learn such low-level TeX. –  Harald Hanche-Olsen Apr 29 '10 at 20:13
In any case, I think MO is very much the wrong place to ask fundamental (La)TeX questions, so I am voting to close. –  Harald Hanche-Olsen Apr 29 '10 at 20:15
The site detexify.kirelabs.org/classify.html is also useful: you can draw a symbol using the mouse and it tries to identify the LaTeX command (and the package you need to use). –  José Figueroa-O'Farrill Apr 29 '10 at 22:41

(Too long for a comment!)

You can have access to essentially every glyph in every font installed, assuming you have sufficient strong will. In this case, you can so something like:

  \documentclass{article}
\DeclareMathSymbol{\funnyobrace}{\mathopen}{largesymbols}{"3C}
\DeclareMathSymbol{\funnycbrace}{\mathclose}{largesymbols}{"3D}
\begin{document}
This is badly aligned, as expected: $\funnyobrace a,b\funnycbrace$.
\end{document}


You could scale the character using graphic tricks, and change its baseline so that it aligns more or less correctly, & so on... At that point you will start wondering if it is worth it!

-
\DeclareMathSymbol{\myfunnyname}{\typeofsymbol}{fontname}{"position}

• \myfunnyname is hopefully obvious
• \typeofsymbol says what sort of a thing it is; typical values being \mathbin (binary operation), \mathrel (relation), \mathalpha (ordinary letter)
• fontname: each table should have a name above it. However, the fontname might not be actually what's there so this may take some digging in the amsfonts style files.
• position: this is the x-y coordinate of the glyph that you want.

Incidentally, the two glyphs you point to aren't actually intended for use by themselves. They are part of what makes up the stretchy braces that you get when you do \big\{ and similar.

-
It seems to be annoyingly non-trivial to deduce "fontname" from any of the information I have (amsfndoc.pdf, or the full ams fonts download)... The names above the tables definitely don't seem to work. On the other hand, Polak's comment above probably makes this irrelevant, because the document he links to is amazingly extensive. –  Dan Ramras Apr 29 '10 at 23:40
I must admit that I assumed you already knew of that! Everyone should know of that document. –  Loop Space Apr 30 '10 at 6:17
Yeah, I'm amazed/embarrassed I didn't know about it. Especially considering that when I went to download it, I tried to save it and found that there was already a copy on my desktop...which I honestly can't recall ever opening. –  Dan Ramras Apr 30 '10 at 6:38
If you have a standard TeX installation, try the 'texdoc' command, or for those who grew up in the post-console days, 'texdoctk'. It's a great way of finding TeX documentation on your system. –  Loop Space Apr 30 '10 at 6:47