See The Comprehensive Symbol List. Examples:
MnSymbol
\documentclass{article}
\usepackage{MnSymbol}
\begin{document}
$\rightmodels\leftmodels$
\end{document}
mathabx
\documentclass{article}
\usepackage{mathabx}
\begin{document}
$\vDash\Dashv$
\end{document}
Symbol composition a la LaTeX
See Enrico Gregorio's comment. The definition of \models
in LaTeX joins a vertical line |
with the double horizontal line \RelBar
.
\documentclass{article}
\DeclareRobustCommand*{\tautequiv}{%
\mathrel{|}\joinrel\Relbar
\Relbar\joinrel\mathrel{|}%
}
\begin{document}
\[ \tautequiv^{\tautequiv^{\tautequiv}} \]
\end{document}
\reflectbox
If the current math fonts do not provide the mirrored \models
, then package graphics
can help:
\documentclass{article}
\usepackage{graphicx}
\newcommand*{\tautequiv}{%
\models\mirrormodels
}
\makeatletter
\newcommand*{\mirrormodels}{%
\mathrel{%
\mathpalette\reflectmathsymbol\models
}%
}
\newcommand*{\reflectmathsymbol}[2]{%
\reflectbox{$\m@th#1#2$}%
}
\makeatother
\begin{document}
\[ \tautequiv^{\tautequiv^{\tautequiv}} \]
\end{document}
Package accsupp
The /ActualText
feature of the PDF format improves the copy&paste behaviour for PDF viewers the support this feature (e.g. Adobe Reader). Example:
\documentclass{article}
\usepackage{accsupp}
\DeclareRobustCommand*{\tautequiv}{%
\BeginAccSupp{unicode,method=hex,ActualText=22A8 2AE4}%
\mathrel{|}\joinrel\Relbar
\Relbar\joinrel\mathrel{|}%
\EndAccSupp{}%
}
\begin{document}
\[ \tautequiv^{\tautequiv^{\tautequiv}} \]
\end{document}
Semantically, don't use either. Use \conj
, or \mean
, or \variant
or whatever the overline is meant to mean. Then in your preamble, do:
\newcommand*\conj[1]{\bar{#1}}
\newcommand*\mean[1]{\bar{#1}}
Then:
- Your document source becomes readable: you can determine the meaning right there and then.
- Your document becomes more flexible: if you decide to denote complex conjugation by a star instead you can simply redefine
\conj
without worrying about changing what \mean
does.
- You can change from
\bar
to \overline
on a whim and don't have to make that crucial decision now.
Best Answer
\models
in the standard fonts is a made up symbolSo you could do a matching combination: