7

I would like to write something of the sort. It's a form of an accent but I do not know how to write letters instead of just dots or a tilde.

Thank youenter image description here

Konrad Rudolph
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Mark Pace
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4 Answers4

13
\documentclass{article}
\usepackage{stackengine,graphicx}
\begin{document}
$\ensurestackMath{\stackengine{.5pt}{\tau}{\scriptscriptstyle e-m}
  {O}{c}{F}{F}{S}}$
or
$\ensurestackMath{\stackengine{1pt}{\tau}{\scalebox{.5}{$\scriptscriptstyle e-m$}}
  {O}{c}{F}{F}{S}}$
\end{document}

enter image description here

With a definition like \newcommand\overtext[2]{\ensurestackMath{\stackengine{1pt}{#1}% {\scalebox{.5}{$\scriptscriptstyle #2$}}{O}{c}{F}{F}{S}}}, a simple invocation of $\overtext{\tau}{e-m}$ accomplishes the task.

If the overset is actually text over a long tilde...

\documentclass{article}
\usepackage{stackengine,graphicx,scalerel,wasysym}
\newcommand\overtext[2]{%
  \savestack\tmp{$\scriptscriptstyle \reallywidealttilde{#2}$}
  \ensurestackMath{\stackengine{.5pt}{#1}%
    {\scalebox{.5}{\tmp}}{O}{c}{F}{F}{S}}}
\newcommand\reallywidealttilde[1]{\ThisStyle{%
  \setbox0=\hbox{$\SavedStyle#1$}%
  \stackengine{.5pt}{$\SavedStyle#1$}{%
    \stretchto{\scaleto{\SavedStyle\mkern.2mu\AC}{.5150\wd0}}{.6\ht0}%
  }{U}{c}{F}{T}{S}}}
\begin{document}
$\overtext{L}{e-m}$ versus $\overtext{L}{x}$ versus $\overtext{L}{Ax^2 + Bx + C}$
\end{document}

enter image description here

The \reallywidealttilde macro is based on my answer at Big tilde in math mode.

10

Here are three additional possibilities. They vary in (a) the symbol used to connect "e" and "m" -- a mathematical minus sign or a simple dash -- and (b) the size of the superscript material -- \scriptsize or \tiny. Not knowing what "e-m" stands for, I don't dare offer an opinion on which form is best.

enter image description here

\documentclass{article}
\usepackage{amsmath}
\begin{document}
$\overset{\mathit{e-m}}{\mathcal{T}}$
$\overset{\textit{e-m}}{\mathcal{T}}$
$\overset{\textit{\tiny e-m}}{\mathcal{T}}$
\end{document}
Mico
  • 506,678
6

I see it as L with a tilde, but it can easily be changed to tau.

\documentclass{article}
\usepackage{stackengine}
\newcommand\tauem{\widetilde{\rule{4pt}{0pt}L\rule{4pt}{0pt}}\raisebox{1.1em}{\kern-15pt\tiny\ensuremath{e-m}}}
\begin{document}
$A\tauem B$
\end{document}

enter image description here

StefanH
  • 13,823
  • Thank you what I used was this: \newcommand\tauem{{\rule{4pt}{0pt}\mathcal{T}\rule{4pt}{0pt}}\raisebox{1.1em}{\kern-15pt\tiny\ensuremath{e-m}}} $\tauem$ – Mark Pace Nov 02 '16 at 14:04
6

This only works in normal style, but I'd avoid using such symbols in subscripts or superscripts anyway.

\documentclass{article}
\usepackage{amsmath}

\newlength{\overtildewd}
\newlength{\overtildewdaux}
\newcommand{\overtilde}[2]{%
  \begingroup
  \settowidth\overtildewd{$\scriptscriptstyle#1$}%
  \settowidth\overtildewdaux{$\textstyle#2$}%
  \ifdim\overtildewdaux>\overtildewd\setlength{\overtildewd}{\overtildewdaux}\fi
  \overset{\scriptscriptstyle#1}{%
    \widetilde{\makebox[\overtildewd]{$\textstyle#2$}}%
  }%
  \endgroup
}

\begin{document}
\[
\overtilde{e}{L}\qquad\overtilde{e-m}{L}
\]
\end{document}

This measures the text above the tilde and the base, getting the widest. Then \widetilde is applied to a box containing the base set centered in a box with the required width, and we apply \overset for setting the part above the tilde.

enter image description here

If the symbol is just a T (maybe calligraphic), there's not much more than \overset; you might just want to make the upper material smaller.

\documentclass{article}
\usepackage{amsmath}

\begin{document}

\[
\overset{e-m}{\mathcal{T}}\qquad
\overset{\scriptscriptstyle e-m}{\mathcal{T}}
\]

\end{document}

enter image description here

egreg
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