Replace all accented characters by their LaTeX equivalent

问题

Given a Unicode string, I want to replace non-ASCII characters by LaTeX code producing them (for example, having é become \'e, and œ become \oe). I'm incorporating this into a Python code. This should rely on a translation table, and I have come up with the following code, which is simple and seems to work nicely:

accents = [
    [ u"à", "\\`a"],
    [ u"é", "\\'e"]
  ]
translation_table = dict([(ord(k), unicode(v)) for k, v in accents])
print u"été à l'eau".translate(translation_table)

But, writing a rather complete translation table will take me a long time, and Google didn't help much. Does someone have such a thing ready, or know where to find one?

PS: I'm new to Python, so I welcome comments on the code above, of course.

回答1:

Download the Unicode Character Database (about 1MB). you can find a relational table for equivalent character combination for example é = \u00E9 is e+ ́ that is equivalent to \u0065+\u0301 (LATIN SMALL LETTER E+COMBINING ACUTE ACCENT). you can write simple codes for converting all combinational characters of all scripts or just them you want (you can control by script field in database).

Then replace the combinations with LaTeX code. for example use regular expression \w\u0065 to replace diactrics :\'<the_letter>. (I'm not sure about syntax. It depends on your programming language and regular expression engine.)

EDIT: If you are using python, you have already the database and an implementation of a handler to use it. just like mentioned in below comment, import unicodedata.

回答2:

OK, so here's the table I've built up for now. Please feel free to edit to add to it! (or comment if you don't have enough reputation to edit)

################################################################
# LaTeX accents replacement
latexAccents = [
  [ u"à", "\\`a" ], # Grave accent
  [ u"è", "\\`e" ],
  [ u"ì", "\\`\\i" ],
  [ u"ò", "\\`o" ],
  [ u"ù", "\\`u" ],
  [ u"ỳ", "\\`y" ],
  [ u"À", "\\`A" ],
  [ u"È", "\\`E" ],
  [ u"Ì", "\\`\\I" ],
  [ u"Ò", "\\`O" ],
  [ u"Ù", "\\`U" ],
  [ u"Ỳ", "\\`Y" ],
  [ u"á", "\\'a" ], # Acute accent
  [ u"é", "\\'e" ],
  [ u"í", "\\'\\i" ],
  [ u"ó", "\\'o" ],
  [ u"ú", "\\'u" ],
  [ u"ý", "\\'y" ],
  [ u"Á", "\\'A" ],
  [ u"É", "\\'E" ],
  [ u"Í", "\\'\\I" ],
  [ u"Ó", "\\'O" ],
  [ u"Ú", "\\'U" ],
  [ u"Ý", "\\'Y" ],
  [ u"â", "\\^a" ], # Circumflex
  [ u"ê", "\\^e" ],
  [ u"î", "\\^\\i" ],
  [ u"ô", "\\^o" ],
  [ u"û", "\\^u" ],
  [ u"ŷ", "\\^y" ],
  [ u"Â", "\\^A" ],
  [ u"Ê", "\\^E" ],
  [ u"Î", "\\^\\I" ],
  [ u"Ô", "\\^O" ],
  [ u"Û", "\\^U" ],
  [ u"Ŷ", "\\^Y" ],
  [ u"ä", "\\\"a" ],    # Umlaut or dieresis
  [ u"ë", "\\\"e" ],
  [ u"ï", "\\\"\\i" ],
  [ u"ö", "\\\"o" ],
  [ u"ü", "\\\"u" ],
  [ u"ÿ", "\\\"y" ],
  [ u"Ä", "\\\"A" ],
  [ u"Ë", "\\\"E" ],
  [ u"Ï", "\\\"\\I" ],
  [ u"Ö", "\\\"O" ],
  [ u"Ü", "\\\"U" ],
  [ u"Ÿ", "\\\"Y" ],
  [ u"ç", "\\c{c}" ],   # Cedilla
  [ u"Ç", "\\c{C}" ],
  [ u"œ", "{\\oe}" ],   # Ligatures
  [ u"Œ", "{\\OE}" ],
  [ u"æ", "{\\ae}" ],
  [ u"Æ", "{\\AE}" ],
  [ u"å", "{\\aa}" ],
  [ u"Å", "{\\AA}" ],
  [ u"–", "--" ],   # Dashes
  [ u"—", "---" ],
  [ u"ø", "{\\o}" ],    # Misc latin-1 letters
  [ u"Ø", "{\\O}" ],
  [ u"ß", "{\\ss}" ],
  [ u"¡", "{!`}" ],
  [ u"¿", "{?`}" ],
  [ u"\\", "\\\\" ],    # Characters that should be quoted
  [ u"~", "\\~" ],
  [ u"&", "\\&" ],
  [ u"$", "\\$" ],
  [ u"{", "\\{" ],
  [ u"}", "\\}" ],
  [ u"%", "\\%" ],
  [ u"#", "\\#" ],
  [ u"_", "\\_" ],
  [ u"≥", "$\\ge$" ],   # Math operators
  [ u"≤", "$\\le$" ],
  [ u"≠", "$\\neq$" ],
  [ u"©", "\copyright" ], # Misc
  [ u"ı", "{\\i}" ],
  [ u"µ", "$\\mu$" ],
  [ u"°", "$\\deg$" ],
  [ u"‘", "`" ],    #Quotes
  [ u"’", "'" ],
  [ u"“", "``" ],
  [ u"”", "''" ],
  [ u"‚", "," ],
  [ u"„", ",," ],
]

回答3:

If you are not in control of LaTeX compilation options, you can use the same table used by the inputenc package, so that the behavior will be the same as if you had used inputenc.

This document explains how inputenc does the mapping, it is a sequence of

...
194 hall; t1; ly1i\DeclareUnicodeCharacter{00C2}{\^A}
195 hall; t1; ly1i\DeclareUnicodeCharacter{00C3}{\~A}
196 hall; t1; ly1i\DeclareUnicodeCharacter{00C4}{\"A}
197 hall; t1; ot1; ly1i\DeclareUnicodeCharacter{00C5}{\r A}
198 hall; t1; ot1; ly1; lcyi\DeclareUnicodeCharacter{00C6}{\AE}
199 hall; t1; ly1i\DeclareUnicodeCharacter{00C7}{\c C}
200 hall; t1; ly1i\DeclareUnicodeCharacter{00C8}{\@tabacckludge`E}

You could parse the file looking for all the DeclareUnicodeCharacter lines and extract with a regexp the mapping.

EDIT: I've written some code that does the trick:

# -*- coding: utf-8 -*-
import re

translation_table = {}

for line in open('utf8ienc.dtx'):
    m = re.match(r'%.*\DeclareUnicodeCharacter\{(\w+)\}\{(.*)\}', line)
    if m:
        codepoint, latex = m.groups()
        latex = latex.replace('@tabacckludge', '') # remove useless (??) '@tabacckludge'
        translation_table[int(codepoint, 16)] = unicode(latex)

print u"été à l'eau".translate(translation_table)

# outputs "\'et\'e \`a l'eau"

You should find utf8ienc.dtx in your latex installation, or you can google it.

回答4:

perhaps not translate the characters but use the inputenc package and the unicode text as is

来源：https://stackoverflow.com/questions/4578912/replace-all-accented-characters-by-their-latex-equivalent