13

I wish to use the symbol as in the following picture, however, I can not find it. Can someone help me?

enter image description here

bersanri
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sweetyBaby
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    What have you tried for finding the symbol (so people don't have to duplicate your efforts)? – Jake Jun 27 '13 at 13:31
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    In particular, you should look at http://tex.stackexchange.com/q/14/86 and see if you can find it using one of the methods there. If you can't, you should say so in the question. – Andrew Stacey Jun 27 '13 at 13:32
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    I use this tool http://detexify.kirelabs.org/classify.html, and also I have tried to find in some documents which map the symbols to latex code. Thanks. – sweetyBaby Jun 27 '13 at 13:33
  • @AndrewStacey Don't think this is in the Detexify database (doesn't seem to cover the necessary packages) – Joseph Wright Jun 27 '13 at 14:09

2 Answers2

18

The symbols is called \Coloneqq in the package txfonts/pxfonts. Here is the rest of the symbols:

enter image description here

Pouya
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13

mathtools package has these symbols with the following argument

The font packages txfonts and pxfonts provides various symbols that include a verti cally centered colon but with tighter spacing. For example, the combination := exists as the symbol \coloneqq which typesets as <tighter symbol picture> instead of <larger symbol picture>. The primary disadvantage of using these fonts are the support packages’ lack of support for amsmath (and thus mathtools) and worse yet, the side-bearings are way too tight; see [4] for examples. If you’re not using these fonts, mathtools provides the symbols for you.

Here is a sample 

\documentclass{article}
\usepackage{mathtools}


\begin{document}

\[\coloneqq \Coloneqq \coloneq \Coloneqq
\eqqcolon \Eqqcolon \eqcolon \Eqcolon
\colonapprox \Colonapprox \colonsim \Colonsim
\dblcolon
\]
\end{document}

enter image description here

percusse
  • 157,807
  • newtx and newpx replace txfonts and pxfonts (respectively), with far better metrics (inc. sidebearings). doesn't help with the interaction with amsmath, though, afaik – wasteofspace Jun 27 '13 at 16:11