69

What is the correct way to make the "does not divide" symbol in plain LaTeX 2e?

I'm talking about the symbol that is a vertical bar with a slash through it. I prefer not to install AMS or other packages, but instead to use plain LaTeX.

Improve this question
3

6 Answers 6

Reset to default
90

Try this:

$x\nmid y$

It has been known to 'save the day'.

Improve this answer
2
  • That doesn't work in plain LaTeX. Do you know what package must be loaded to make it work? I tried \usepackage{amsfonts} but that doesn't work. And I still prefer a plain LaTeX solution.
    – user448810
    Aug 5, 2011 at 22:33
  • 12
    I got \nmid working with \usepackage{amssymb}.
    – user448810
    Aug 5, 2011 at 22:46
18

Detexify is amazingly helpful in finding any symbol.

Improve this answer
0
6

Using \not with | works with plain LaTeX:

\documentclass{article}
\begin{document}
$2 \not| \;3 $
\end{document}

The symbols \\, and \: and \; create varying degrees of space if the symbols get too close.

Improve this answer
6
  • I wonder why the \not introduces so much space.
    – Dylan Moreland
    Jun 22, 2012 at 1:11
  • 2
    I'm not sure which space you're talking about but try this: $2 \!\!\not| \,3 $. The \! is negative space to get things closer together on the right and \, will reduce space on the right
    – DJP
    Jun 22, 2012 at 1:26
  • 1
    Oh, I didn't think you'd come back to this! Thanks very much. I just meant that while a|b is nice and compact, a\not|b puts a strange amount of space between a and |.
    – Dylan Moreland
    Jun 22, 2012 at 1:28
  • 1
    I don't know why \not has so much extra space but if I had to guess it might be because \not can be used in conjunction with a lot of other symbols which are wider than | [eg \not\in or \not\subset]. So some combinations will look better than others depending on the symbol width being negated.
    – DJP
    Jun 22, 2012 at 1:48
  • The spacing on \not\mid was ok when I used it on mathoverflow (mathoverflow.net/questions/256598/…)
    – theHigherGeometer
    Dec 7, 2016 at 7:41
4

To minimize used packages you can do this:
\newcommand{\ndiv}{\hspace{-4pt}\not|\hspace{2pt}}
From then on \ndiv will add the sign with appropriate spaces before and after.

Improve this answer
3
  • 3
    If the font size changes, this can cause a lot of headache. At least you can opt for units like ex,em but still it would not be robust enough to be used elsewhere.
    – percusse
    Nov 27, 2012 at 1:11
  • @percusse: can you provide a more robust way?
    – cxxl
    May 23, 2013 at 8:02
  • 1
    @cxxl The answers above are pretty good. Otherwise you can look for the definitions from the LaTeX versions and carry them to plain TeX as raw macros.
    – percusse
    May 23, 2013 at 20:55
4

The ∤ symbol is available in Unicode as U+2224 Does Not Divide, and as \nmid from many packages, including: unicode-math, amssymb, stix, stix2, newtxmath and the less commonly-usedmnsymbol, fdsymbol and boisk.

Improve this answer
0

After fine tuning, I'm pretty happy with defining a new command \doesnotdivide (or whatever you'd like to name it) as: \newcommand{\doesnotdivide}{\not\hspace{2.5pt}\mid}

I found that three points was too much and 2 points was not enough offset.

Improve this answer
1
  • 1
    This is somewhat similar to blerbl's answer. Note that a comment there points out that measuring in em would be better than pt, since it would automatically adjust to a change in font size.
    – Teepeemm
    May 2, 2019 at 0:23

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.