![提取每个单词的首字母,包括破折号等特殊字符后的首字母](https://linux22.com/image/337276/%E6%8F%90%E5%8F%96%E6%AF%8F%E4%B8%AA%E5%8D%95%E8%AF%8D%E7%9A%84%E9%A6%96%E5%AD%97%E6%AF%8D%EF%BC%8C%E5%8C%85%E6%8B%AC%E7%A0%B4%E6%8A%98%E5%8F%B7%E7%AD%89%E7%89%B9%E6%AE%8A%E5%AD%97%E7%AC%A6%E5%90%8E%E7%9A%84%E9%A6%96%E5%AD%97%E6%AF%8D.png)
这个问题基于这个答案。
发现字母出现在破折号旁边时缺失,如以下 MWE 所示:
\documentclass{article}
\usepackage{readarray}
\usepackage{ifthen}
\newcounter{index}\setcounter{index}{0}
\def\firstletters#1{%
\getargsC{#1}%
\whiledo{\theindex<\narg}{%
\stepcounter{index}%
\edef\nextword{\csname arg\romannumeral\theindex\endcsname}%
\expandafter\getfirst\nextword\relax%
}%
}
\def\getfirst#1#2\relax{#1}
\begin{document}
\firstletters{This is a test of the Emergency Broadcast System. This-Test. for sample. This T.}
\end{document}
答案1
这datatool
软件包提供了\DTLinitials
。例如:
\documentclass{article}
\usepackage{datatool-base}
\begin{document}
\DTLinitials{This is a test of the Emergency Broadcast System.
This-Test. for sample. This T.}
\end{document}
这会自动在每个首字母后插入一个句点,但可以通过重新定义 和 来防止这种\DTLafterinitials
情况\DTLbetweeninitials
发生\DTLafterinitialbeforehyphen
。
\documentclass{article}
\usepackage{datatool-base}
\renewcommand*{\DTLbetweeninitials}{}
\renewcommand*{\DTLafterinitials}{}
\renewcommand*{\DTLafterinitialbeforehyphen}{}
\begin{document}
\DTLinitials{This is a test of the Emergency Broadcast System.
This-Test. for sample. This T.}
\end{document}
如果您需要可扩展上下文中的首字母缩写,则首先需要使用\DTLstoreinitials
,它将在第二个参数提供的命令中保存首字母缩写:
\DTLstoreinitials{This is a test of the Emergency Broadcast System.
This-Test. for sample. This T.}{\initials}
\initials
编辑:如果您还想从首字母中删除连字符,只需重新定义\DTLinitialhyphen
为不执行任何操作即可:
\renewcommand*{\DTLinitialhyphen}{}
编辑 2:请注意,它\DTLinitials
主要用于名称(其最初目的是与 提供的缩写书目样式一起使用databib
),因此它假定其参数是一系列由空格或连字符分隔的字母。此外,从手动的:
如果首字母带有重音,请小心。如果您希望首字母也带有重音,则需要将带重音的字母放在一个组中,否则重音命令将被忽略。
因此,根据您下面的评论:
\DTLinitials{{\"{O}}zg\"{u}r}
或者使用 XeLaTeX 或 LuaLaTeX 和 UTF-8 字符。这类似于\makefirstuc
(来自mfirstuc
)的限制
另请参阅datatool
手册:
事实上,任何出现在名称开头且未被组括起来的命令都会被忽略。
这意味着,
\DTLinitials{\MakeUppercase{m}ary ann}
会产生ma不是Ma
答案2
以下是仅基于经典 TeX 的解决方案:
\def\firstletters{\bgroup \catcode`-=10 \catcode`(=10 \filA}
\def\filA#1{\filB#1 {\end} }
\def\filB#1#2 {\ifx\end#1\egroup \else#1\expandafter\filB\fi}
\firstletters{This is a test of the Emergency Broadcast System.
This-Test. for sample (per se). This T.}
\bye
答案3
使用正则表达式,我们可以删除从字母到空格或连字符的所有内容。
\documentclass{article}
\usepackage{xparse,l3regex}
\ExplSyntaxOn
\NewDocumentCommand{\firstletters}{m}
{
\kumaresh_firstletters:n { #1 }
}
\tl_new:N \l_kumaresh_fl_input_tl
\cs_new_protected:Nn \kumaresh_firstletters:n
{
\tl_set:Nn \l_kumaresh_fl_input_tl { #1 ~ }
\regex_replace_all:nnN { ([A-Za-z]).*?[-\s]} { \1 } \l_kumaresh_fl_input_tl
\tl_use:N \l_kumaresh_fl_input_tl
}
\ExplSyntaxOff
\begin{document}
\firstletters{This is a test of the Emergency Broadcast System. This-Test. for sample. This T.}
\end{document}
答案4
这是另一个基于 LuaLaTeX 的解决方案。它测试字符串是否包含任何字母字符,如果没有找到字母字符,则不执行任何操作。它不假设字符串的第一个字符是字母类型字符。建议的解决方案可以处理非 ASCII 编码的字母,例如ä
、Ä
和Å
。
\documentclass{article}
\usepackage{fontspec}
\usepackage{luacode} % for 'luacode' env. and '\luaexec' macro
\begin{luacode}
local i, w , wstring
function fl ( s )
i = unicode.utf8.find ( s , "%w")
-- Do nothing if i=="nil", i.e., if 's' doesn't
-- contain at least one alphabetical character:
if i ~= nil then
-- Pick up the first letter of first word:
wstring = unicode.utf8.sub ( s , i , i )
s = unicode.utf8.sub ( s , i+1 )
-- Pick up the first letters of all remaining words:
for w in unicode.utf8.gmatch ( s , "%W%w" ) do
wstring = wstring .. unicode.utf8.sub ( w , 2 )
end
tex.sprint ( wstring )
end
end
\end{luacode}
\newcommand{\firstletter}[1]{\luaexec{fl(\luastring{#1})}}
\begin{document}
\firstletter{This is a test of the Emergency Broadcast System. This-Test. for sample. This T. per se}
% Same string, but with additional non-letter characters
\firstletter{@--?#&$() []<>^_ This is a test of the
Emergency Broadcast System. This--Test.
for sample. This T.
(per se)}
% Words that start with non-ASCII-encoded characters
\firstletter{$$$ähnlich "öffentlich *übrigens !?<>Äpfel
Özgür ((((^Übung .ßcheusslich+++ ,===Ångstrom}
\firstletter{!@#$^&*()!@#$^&*()_+-={}[]|\\;<>?Ö}
% Two strings without any "words"
a\firstletter{"("§$&/)@@=}b\firstletter{}c
\end{document}