[LaTex] 上划线输入

转载自 http://blog.sina.com.cn/s/blog_5e16f1770100lz4e.html

\documentclass{article}
\usepackage{amsmath}
\usepackage{accents}
\usepackage{statex}
\makeatletter
\def\wideubar{\underaccent{{\cc@style\underline{\mskip10mu}}}}
\def\Wideubar{\underaccent{{\cc@style\underline{\mskip8mu}}}}
\makeatother

\makeatletter
\def\widebar{\accentset{{\cc@style\underline{\mskip10mu}}}}
\def\Widebar{\accentset{{\cc@style\underline{\mskip8mu}}}}
\makeatother


\begin{document}

$
\bar{X}_i
\overline{X}_i
\widebar{X}_i
\Widebar{X}_i
\b{X_i}
\ol{X_i}
$



$
\underline{X}_i
\wideubar{X}_i
\Wideubar{X}_i
\ul{X}_i
$

\end{document}