1

I encountered the following equality symbol in a paper (page 4, Eq 4). I am not sure how it is different from a regular equality (=) symbol.

enter image description here

What does this symbol mean? And how can I write it in latex?

Community
  • 1
vyi
  • 111
  • 2
    meaning of the mathematics is off topic here sorry, a tex question of how to typeset that would be on topic. (If I knew the meaning I'd have mentioned it here) – David Carlisle Oct 29 '19 at 23:58
  • Off topic: maybe it is only to explain from where that equality comes. Look for some equation named as (!). – Sigur Oct 29 '19 at 23:59
  • @DavidCarlisle Thanks for your input. Since you mentioned, I feel interested in how one would go about writing that symbol. – vyi Oct 30 '19 at 00:00
  • @Sigur I have flagged the post for migration. Thank you. – vyi Oct 30 '19 at 00:03

1 Answers1

3

OP comments: "I feel interested in how one would go about writing that symbol"

\documentclass{article}
\usepackage{stackengine}
\def\bangequal{\mathrel{\ensurestackMath{%
  \stackengine{1pt}{=}{\scriptstyle!}{O}{c}{F}{F}{S}}}}
\begin{document}
$a \bangequal b$
\end{document}

enter image description here

To get the particularly ugly version where the ! is underlined...

\documentclass{article}
\usepackage{stackengine}
\def\bangequal{\mathrel{\ensurestackMath{%
  \stackengine{0pt}{=}{\underline{\scriptstyle!}}{O}{c}{F}{F}{S}}}}
\begin{document}
$a \bangequal b$
\end{document}

enter image description here

Steven B. Segletes
  • 237,551