答案1
以下是其中之一:
\documentclass{article}
\usepackage{mathtools, amssymb}
\DeclareFontFamily{U}{matha}{\hyphenchar\font45}
\DeclareFontShape{U}{matha}{m}{n}{ <-6> matha5 <6-7> matha6 <7-8>
matha7 <8-9> matha8 <9-10> matha9 <10-12> matha10 <12-> matha12 }{}
\DeclareSymbolFont{matha}{U}{matha}{m}{n}
\DeclareMathSymbol{\myvee}{\mathbin}{matha}{"5F}
\newcommand{\myveebar}{\mathbin{\vcenter{\hbox{$ \underline{\mkern-2.4mu{\myvee}\mkern-2.4mu} $}}}}
\begin{document}
\[ K \myveebar A\]
\end{document}
答案2
这是另一个(上标未缩放):
\documentclass[border=1pt]{standalone}
\usepackage{stackengine,mathabx}
% \newcommand{\veebaralt}{\:\stackanchor[-.22em]{$\vee$}{$-$}\:}
\newcommand{\veebaralt}{\mathrel{\ensurestackMath{\renewcommand\stacktype{S}\stackanchor[-.22em]{\vee}{-}}}}
\begin{document}
$123 \veebaralt 123$
$123 \veebar 123$
\end{document}
编辑:\:
在旧命令之前和之后添加;添加史蒂文·B·塞格莱特斯' 有帮助的答案。
答案3
我自己刚刚盲目地想出了一个可能的解决方案,所有的功劳都归于egreg 的回答在不等号下的虚线下划线,改编自:
\documentclass{article}
\usepackage{pict2e,picture}
\usepackage{mathabx}
\makeatletter
\newcommand{\barredeq}[1]{\mathrel{\vphantom{\veebar}\mathpalette\barred@eq{#1}}}
\newcommand{\barred@eq}[2]{%
\vcenter{%
\offinterlineskip
\roundcap
\linethickness{0.6\dimexpr\variable@rule{#1}\relax}%
\sbox\z@{$\m@th#1#2$}%
\setlength{\unitlength}{\dimexpr(\wd\z@-2\dimexpr\barred@eq@kern{#1})/10}%
\sbox\tw@{\begin{picture}(1,0)\Line(0,0)(10,0)\end{picture}}%
\ialign{%
##\cr
\copy\z@\cr
\noalign{\vskip 0.25\ht\z@}
\kern\barred@eq@kern{#1}%
\copy\tw@
\kern\barred@eq@kern{#1}%
\cr
}%
}%
}
\newcommand{\barred@eq@kern}[1]{%
\ifx#1\displaystyle 0.12\wd\z@\else
\ifx#1\textstyle 0.12\wd\z@\else
\ifx#1\scriptstyle 0.18\wd\z@\else
\ifx#1\scriptscriptstyle 0.22\wd\z@\else
0.16\wd\z@
\fi\fi\fi\fi
}
\newcommand{\variable@rule}[1]{%
\fontdimen8
\ifx#1\displaystyle\textfont3\else
\ifx#1\textstyle\textfont3\else
\ifx#1\scriptstyle\scriptfont3\else
\scriptscriptfont3\relax
\fi\fi\fi
}
\makeatother
\DeclareRobustCommand{\nveebar}{\barredeq{\vee}}
\begin{document}
$A\vee A \veebar A\nveebar A$
$\scriptstyle A\vee A \veebar A \nveebar A$
$\scriptscriptstyle A \vee A \veebar A \nveebar A$
\end{document}