Output a relational symbol on LaTeX (precedes under relation, ⊰)

I'm trying to output this character on LaTeX: ⊰ (click here if you can't see it)

The more I search and read the more confused I am. At this point I am clueless.

Supposedly the command is \prurel, but I found no package related to that macro. The \mathrel command is related, but I don't know how, I didn't find a package for that macro either. \UnicodeMathSymbol{"022B0} is related somehow, I couldn't figure which way yet. unicode-math.tex is related to all these things, but I could not find that file in my installation.

I simply hope it is possible to add this without collateral damages (for instance converting all the other symbols to unicode or anything like that).

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Welcome to TeX.sx! – Andrew Swann Jan 9 '13 at 15:50

I'm not an expert at this subject, but after some experimentation and detective work, I've found the following:

• Your guesses about \UnicodeMathSymbol{"022B0}, \prurel and \mathrel seems to be based on the content of the file [...]texmf-dist/tex/latex/unicode-math/unicode-math-table.tex, which contains the following line:

\UnicodeMathSymbol{"022B0}{\prurel}{\mathrel}{element precedes under relation}%

• That file is part of the package unicode-math.

• According with the documentation of that package:

A simple beginning is:

\usepackage{unicode-math}
\setmathfont{xits-math.otf}


So I tried the following MWE:

\documentclass{article}
\usepackage{unicode-math}
\setmathfont{xits-math.otf}
\begin{document}
$a\prurel b$, $c ⊰ d$
\end{document}


which had to be compiled with xelatex or lualatex (because it uses .otf fonts, only supported with those engines), and produced:

The conclusion is then that the macro in question (\prurel) is simply a way to get the symbol from an appropiate math font which contains it, which in this case is xits-math.otf (but the documentation of unicode-math lists other compatible fonts), and it will not work if you don't have an appropiate font.

In addition, since apparently that symbol is implemented only in otf fonts, you would require xelatex or luatex to compile your document. I don't know if this qualifies as "collateral damages" :-)

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Thank you very much, that's perfect. I could have been fighting with pdfTeX for ever. Also my installation seems not to be able to find unicode-math, so I'm going to spend a while with that. Thanks to you now I know what's the goal. – Trylks Jan 9 '13 at 16:52
@Trylks I tried it under texlive 2012 and worked out of the box. – JLDiaz Jan 9 '13 at 17:09
The problem was that my Texniccenter version was terribly outdated, the new one includes LuaLaTex and XeLaTex. Now everything works out of the box. That was faster than I expected :) Thank you again. – Trylks Jan 11 '13 at 15:58

The symbol is \prec and also has a counterpart called \succ. Both are math-symbols and must be written within math mode.

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It's hard to see the difference, but that's a different symbol, you can compare and – Trylks Jan 9 '13 at 15:09
this may be a different symbol. unicode has "precedes" at U+227A, while "precedes under relation" (with the ends distinctly recurved) at U+22B0. (they are cross-referenced in the unicode charts.) \prurel is almost certainly in the xits fonts (that's the name assigned during the stix project). the counterpart (U+22B1) was assigned the name \scurel. – barbara beeton Jan 9 '13 at 15:21