![amsmath 中的复选标记错误](https://linux22.com/image/263784/amsmath%20%E4%B8%AD%E7%9A%84%E5%A4%8D%E9%80%89%E6%A0%87%E8%AE%B0%E9%94%99%E8%AF%AF.png)
这一页说amsmath
支持该\checkmark
符号。然而,当我尝试实现这个
\documentclass[12pt]{article}
\usepackage{amsmath}
\begin{document}
$\checkmark$
\end{document}
TeXWorks 给出了错误
! Undefined control sequence.
recently read> \checkmark
这里可能存在什么问题?谢谢大家。
答案1
该页面有误。那里列出的所有符号名称均来自amsfonts
。
原始实现amsmath
(然后amstex.sty
在非乳胶原件后调用)已加载amsfonts
,但amsmath
没有。来自文件amsmath.dtx
:
% A \latex/ package named \pkg{amstex} was created in 1988--1989 by
% adapting \fn{amstex.tex} for use within \latex/. The \pkg{amsmath}
% package is the successor of the \pkg{amstex} package. It was
% substantially overhauled to integrate it with \latex/2e, which
% arrived on the scene in 1994. It provides more or less the same
% features, but there are quite a few organizational differences as
% well as some new features and bug fixes. For example, the
% \pkg{amstex} package automatically loaded the \pkg{amsfonts}
% package, but the \pkg{amsmath} package does not. At the present
% time (November 1999) user-level documentation of the commands
% provided here is found in the AMSmath Users' Guide,
% \fn{amsldoc.tex}.
因此有必要\usepackage{amsfonts}
访问\checkmark
。所引用页面的其余大部分内容都指定了amssymb
,这是正确的;会自动amssymb
加载amsfonts
,因此如果需要附加符号,则无需同时指定两者。
您知道谁负责该页面吗?最好让他们知道应该更正/更新。