emacs auctex: how to get \frac{}{} and \bm{}?

Question

How can I find out (in AUCTeX) if \frac{}{} and \bm{} have predefined keyboard shortcuts? I couldn't find these two.

Answer 1

I can't find anything like that in the auctex documentation, but if you'd like to have shortcuts for them, add the following lines to your .xemacs/init.el file (if you use xemacs) or your .emacs file (if you use emacs):

(defun insert-frac ()
  "We insert  \\frac{}{} and position point before the first right brace."
  (interactive)
  (progn
    (insert "\\frac{}{}")
    (backward-char)
    (backward-char)
    (backward-char)))
;;--------------------------------------------------------------------
(defun insert-bm ()
  "We insert  \\mb{} and position point before the right brace."
  (interactive)
  (progn
    (insert "\\bm{}")
    (backward-char)))
;--------------------------------------------------------------------
(global-set-key "\C-cf"   'insert-frac)
(global-set-key "\C-cb"   'insert-bm)

You can then insert \frac{}{} and put point inside the first pair of braces by typing Control-c f and you can insert \bm{} and put point inside the braces by typing Control-c b.

Answer 2

You can customize LaTeX-math-list. It takes a key and a string or function as well as some menu definitions. Then after pressing a prefix key (defined by LaTeX-math-abbrev-prefix and by defualt "`") and the key you defined it either inserts the string or runs the function. Thus adding (with Phil's definition of insert-frac)

(?f 'insert-frac "frac" "Constructs")

will make it so that ` f will insert \frac{}{} with the cursor properly positioned. Of course you will no longer be able to insert \phi this way, but you can choose a better key than f.

Looking at LaTeX-math-default shows you all the defaults. By default there is an entry for frac, but no key is assigned to it. There is no default for \bm.

Answer 3

I suggest a snippet. You need less keys and do not block expensive hotkey sequences. After installing yasnippet create this snippet via menu

# -*- mode: snippet -*-
# name: frac
# key: /
# --
\frac{$1}{$2}

and save it in the snippet folder. The filename is just for your eyes. Now you type / TAB and get \frac{|}{} with cursor at |

You can find my complete configuration on github if you get stuck. emacs-config