答案1
这是一个不那么简单™的解决方案:
\documentclass{article}
\usepackage{amsmath,pict2e}
\makeatletter
\newcommand{\raisingcircleseq}{\mathrel{\mathpalette\raising@circles@eq\relax}}
\newcommand{\raising@circles@eq}[2]{%
\vphantom{#1+}%
\vbox{
\settowidth\unitlength{$#1\mspace{2mu}$}%
\offinterlineskip\m@th
\ialign{##\cr
\hfil\small@circle{#1}$#1\mspace{1.5mu}$\cr\noalign{\vskip0.5\unitlength}
$#1=$\cr\noalign{\post@vskip{+}{#1}}
$#1\mspace{1.5mu}$\small@circle{#1}\hfill\cr\noalign{\post@vskip{-}{#1}}
}%
}%
}
\newcommand{\small@circle}[1]{%
\smash{%
\begin{picture}(1,1)
\small@linethickness{#1}
\put(0.5,0.5){\circle{1}}
\end{picture}%
}%
}
\newcommand{\small@linethickness}[1]{%
\linethickness{%
\ifx#1\displaystyle 0.8\fontdimen8\textfont3\else
\ifx#1\textstyle 0.8\fontdimen8\textfont3\else
\ifx#1\scriptstyle0.8\fontdimen8\scriptfont3\else
1\fontdimen8\scriptscriptfont3\fi\fi\fi
}%
}
\newcommand{\post@vskip}[2]{%
\expandafter\vskip\expanded{%
#1\ifx#2\scriptscriptstyle0.9\else\ifx#2\scriptstyle0.6\else0.3\fi\fi\unitlength
}%
}
\makeatother
\begin{document}
$a=\raisingcircleseq b$
$a\raisingcircleseq b$
${=\raisingcircleseq}{\scriptstyle=\raisingcircleseq}{\scriptscriptstyle=\raisingcircleseq}$
\end{document}
答案2
这是一个选择。
\documentclass{article}
\usepackage{amsmath, amssymb}
\usepackage{graphicx}
\newlength{\circheight}
\settoheight{\circheight}{\(=\)}
\addtolength{\circheight}{.5pt}
\newcommand*{\smallcirc}{\scalebox{.51}{\(\scriptscriptstyle\boldsymbol{\circ}\)}}
\newcommand*{\risingcircleseq}{%
\mathrel{%
\makebox[0pt][l]{\raisebox{-.5pt}{\smallcirc}}%
\mbox{=}%
\makebox[0pt][r]{\raisebox{\circheight}[0pt]{\smallcirc}}%
}%
}
\begin{document}
\(A \risingcircleseq B\)
\end{document}
答案3
适用于所有数学样式。用于stackengine
构建宏并scalerel
自动处理数学样式。
\documentclass{article}
\usepackage{stackengine,graphicx,scalerel}
\newcommand\eqdots{\mathrel{\ensurestackMath{\ThisStyle{%
\stackengine{-.5\LMpt}{\stackengine{.5\LMpt}{\SavedStyle=}%
{\SavedStyle\scaleobj{.33}{\circ\,}}{O}{r}{F}{T}{S}}%
{\SavedStyle\scaleobj{.33}{\,\circ}}{U}{l}{F}{T}{S}}}}}
\begin{document}
$x\eqdots y$\par
$\scriptstyle x\eqdots y$\par
$\scriptscriptstyle x\eqdots y$\par
\end{document}
答案4
\makebox
具有和 的 解决方案(显示样式)accents
:
\documentclass{article}
\usepackage{makebox}
\usepackage{mathtools}
\usepackage{accents}
\usepackage{calc}
\newcommand{\risingcirceq}{\mathrel{%
\underaccent{\raisebox{-0.5ex}[0pt]{\makebox[\widthof{$=$}][l]{\scalebox{0.6}{$\circ$}}}}{%
\accentset{\raisebox{-0.15ex}[0pt][0pt]{\makebox[\widthof{$=$}][r]{\scalebox{0.6}{$\circ$}}}}{=}}
}}%
\begin{document}
\[ a\risingcirceq b\]%
\end{document}