I'm writing up some notes that will be displayed on an overhead projector. The standard time-derivative \dot{x} produces a dot that is hard to see. Does anyone know of a package or have a macro that produces a (nice looking) larger dot? Similarly with \ddot{x}.

At the moment, I've been supplied with some ugly code that produces an ugly output:

\def\dt#1{{\buildrel  {\hbox{\LARGE . }} \over {#1}}}    % dot-over 
\def\ddt#1{{\buildrel {\hbox{\LARGE ..}} \over {#1}}}    % double dot

You could use the accents package and its command \accentset to create faked accents. Here`s an example:

  \accentset{\mbox{\large\bfseries .}}{#1}}
  \accentset{\mbox{\large\bfseries .\hspace{-0.25ex}.}}{#1}}
$\dot{x} \neq \dt{x}$

$\ddot{x} \neq \ddt{x}$


alt text

Instead of a large bold period you could also choose for instance a tiny \bullet.


The amsmath package provides the commands \overset and \underset to set arbitrary things over/under other arbitrary things. So with amsmath and bm loaded you can use

\overset{\bm .}{a}

to obtain an "a" with a bold dot on it.

  • For a closer dot, with horizontal positioning appropriate to italic characters, you could try \renewcommand{\dot}[1] {\overset{\,_{\mbox{\Large .}}}{#1}} , where \Large may be replaced by another size or \bf, to taste. The effect is easily seen by commenting the \renewcommand in and out. – Gavin R. Putland Jan 7 '20 at 2:17
  • Alternatively, create a \bigdot command with: \newcommand{\bigdot}[1]{\overset{\bm .}{#1}} – Peter Jan 11 '20 at 0:50

The normal \dot uses the dot accent from the font, so switching font families to a font set with larger accents would be the cleanest solution.

  • Can you give an example? Would that also switch the font of the text/math? – Simon Aug 17 '10 at 8:27
  • No, sorry. I do not use LaTeX myself. Anyway, I think Caramdir's answer is better – Taco Hoekwater Aug 17 '10 at 9:48
  • For slides, a sans-serif font might be a good idea, and it may help with the dot problem as well. – Jukka Suomela Aug 17 '10 at 10:39

Maybe rather use \partial_t x or x_t? Also quite compact and much more noticeable.

  • 2
    I agree, but I'm writing the notes for someone else, so I don't get a say in the matter. – Simon Aug 17 '10 at 8:26

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.