答案1
也许这就足够了。(但请注意,如果您想在章节标题中使用它并使用,则需要付出额外的努力hyperref
。)
\documentclass{article}
\usepackage{amssymb}
\usepackage{accents}
\begin{document}
$\accentset{\curvearrowright}{\mathcal{O}}$
\end{document}
我不确定我是否会这么做,但你可以扩展事情。
\documentclass{article}
\usepackage{amssymb}
\usepackage{accents}
\usepackage{graphicx}
\begin{document}
$\accentset{\curvearrowright}{\mathcal{O}}$ $\accentset{\scalebox{1}[0.6]{$\curvearrowright$}}{\mathcal{O}}$
\end{document}
您也可以选择更为复杂的解决方案。
\documentclass{article}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{tikz}
\usetikzlibrary{tikzmark,arrows.meta,bending,calc}
\newcounter{coverarcarrow}
\newcommand{\overarcarrow}[2][]{\stepcounter{coverarcarrow}%
\overset{\vphantom{+}}{\tikzmarknode{coverarcarrow-\number\value{coverarcarrow}}{#2}}%
\begin{tikzpicture}[overlay,remember picture]
\draw let \p1=($(coverarcarrow-\number\value{coverarcarrow}.north east)-(coverarcarrow-\number\value{coverarcarrow}.south west)$),
\n1={atan2(2ex,\x1)} in
[-{Stealth[bend,length={min(0.3*\x1,0.8ex)}]},semithick,#1]
([yshift=0.2*\y1]coverarcarrow-\number\value{coverarcarrow}.north west)
to[out=\n1,in=180] ([yshift=0.8ex]coverarcarrow-\number\value{coverarcarrow}.north)
to[out=0,in={180-\n1}] ([yshift=0.2*\y1]coverarcarrow-\number\value{coverarcarrow}.north east);
\end{tikzpicture}}
\begin{document}
$\overarcarrow{\mathcal{O}}$
$\overarcarrow{\mathcal{O}_1\mathcal{O}_2\cdots\mathcal{O}_n}$
\end{document}
答案2
使用该fourier
包可以看到符号\wideOarc{...}
。我添加了\DeclareMathAlphabet{\mathccal}{OMS}{cmsy}{m}{n}
现代计算机 (CM) 的书法符号:
\documentclass[a4paper,12pt]{article}
\usepackage[OT1]{fontenc}
\usepackage{amsmath,amssymb}
\DeclareMathAlphabet{\mathccal}{OMS}{cmsy}{m}{n}
\usepackage{fourier}
\begin{document}
$\wideOarc{\mathccal{O}}$
\end{document}