Separate pinyin syllables with whitespace. Eg: "nǐhāo" becomes "nǐ hāo" Eg: "Yīlù píng'ān" becomes "Yī lù píng ān"

separate_pinyin.py

# -*- coding: utf-8 -*-
#
# Copyright © 2012 Thomas TEMPÉ, <thomas.tempe@alysse.org>
# 
# License: GNU GPL, version 3 or later; http://www.gnu.org/copyleft/gpl.html

import re

inits = u"zh|sh|ch|[bpmfdtnlgkhjqxrzscwy]"
finals = u"i[ōóǒòo]ng|[ūúǔùu]ng|[āáǎàa]ng|[ēéěèe]ng|i[āɑ̄áɑ́ɑ́ǎɑ̌àɑ̀aāáǎàa]ng|[īíǐìi]ng|i[āáǎàa]n|u[āáǎàa]n|[ōóǒòo]ng|[ēéěèe]r|i[āáǎàa]|i[ēéěèe]|i[āáǎàa]o|i[ūúǔùu]|[īíǐìi]n|u[āáǎàa]|u[ōóǒòo]|u[āáǎàa]i|u[īíǐìi]|[ūúǔùu]n|u[ēéěèe]|ü[ēéěèe]|v[ēéěèe]|i[ōóǒòo]|[āáǎàa]i|[ēéěèe]i|[āáǎàa]o|[ōóǒòo]u|[āáǎàa]n|[ēéěèe]n|[āáǎàa]|[ēéěèe]|[ōóǒòo]|[īíǐìi]|[ūúǔùu]|[ǖǘǚǜüv]"
standalones = u"'[āáǎàa]ng|'[ēéěèe]ng|'[ēéěèe]r|'[āáǎàa]i|'[ēéěèe]i|'[āáǎàa]o|'[ōóǒòo]u|'[āáǎàa]n|'[ēéěèe]n|'[āáǎàa]|'[ēéěèe]|'[ōóǒòo]"
pinyin_re = "(("+inits+")("+finals+")|("+standalones+"))"
pinyin_two_re = re.compile("(?P<one>"+pinyin_re+")(?P<two>"+pinyin_re+")", flags=re.I)


def separate_pinyin(text):
    u"""
    Separate pinyin syllables with whitespace.
    Eg: "nǐhāo" becomes "nǐ hāo"
    Eg: "Yīlù píng'ān" becomes "Yī lù píng ān"
    
    Assumes the pinyin respects the apostrophe/accent's placement rules :
    http://www.pinyin.info/romanization/hanyu/apostrophes.html
    http://www.pinyin.info/rules/where.html

    Respect of these rules guarantee there's no ambiguity in the separation.

    Does not work with tone numbers as suffixed numeral (eg: ni3hao3)

    Useful as pre-processing for Google Translate's output.
    """
    def clean(t):
        'remove leading apostrophe'
        if "'" == t[0]:
            return t[1:]
        return t
    def separate_pinyin_sub(p):
        return clean(p.group("one"))+" "+clean(p.group("two"))
    #Run twice in case of overlapping sequences
    text =  pinyin_two_re.sub(separate_pinyin_sub, text)
    text =  pinyin_two_re.sub(separate_pinyin_sub, text)
    return text

#Demo
#print separate_pinyin(u"Yīlù píng'ān")# -*- coding: utf-8 -*-
#
# Copyright © 2012 Thomas TEMPÉ, <thomas.tempe@alysse.org>
# 
# License: GNU GPL, version 3 or later; http://www.gnu.org/copyleft/gpl.html

import re

inits = u"zh|sh|ch|[bpmfdtnlgkhjqxrzscwy]"
finals = u"i[ōóǒòo]ng|[ūúǔùu]ng|[āáǎàa]ng|[ēéěèe]ng|i[āɑ̄áɑ́ɑ́ǎɑ̌àɑ̀aāáǎàa]ng|[īíǐìi]ng|i[āáǎàa]n|u[āáǎàa]n|[ōóǒòo]ng|[ēéěèe]r|i[āáǎàa]|i[ēéěèe]|i[āáǎàa]o|i[ūúǔùu]|[īíǐìi]n|u[āáǎàa]|u[ōóǒòo]|u[āáǎàa]i|u[īíǐìi]|[ūúǔùu]n|u[ēéěèe]|ü[ēéěèe]|v[ēéěèe]|i[ōóǒòo]|[āáǎàa]i|[ēéěèe]i|[āáǎàa]o|[ōóǒòo]u|[āáǎàa]n|[ēéěèe]n|[āáǎàa]|[ēéěèe]|[ōóǒòo]|[īíǐìi]|[ūúǔùu]|[ǖǘǚǜüv]"
standalones = u"'[āáǎàa]ng|'[ēéěèe]ng|'[ēéěèe]r|'[āáǎàa]i|'[ēéěèe]i|'[āáǎàa]o|'[ōóǒòo]u|'[āáǎàa]n|'[ēéěèe]n|'[āáǎàa]|'[ēéěèe]|'[ōóǒòo]"
pinyin_re = "(("+inits+")("+finals+")|("+standalones+"))"
pinyin_two_re = re.compile("(?P<one>"+pinyin_re+")(?P<two>"+pinyin_re+")", flags=re.I)


def separate_pinyin(text):
    u"""
    Separate pinyin syllables with whitespaces.
    Eg: "nǐhāo" becomes "nǐ hāo"
    Eg: "Yīlù píng'ān" becomes "Yī lù píng ān"
    
    Assumes the pinyin respects the apostrophe/accent's placement rules :
    http://www.pinyin.info/romanization/hanyu/apostrophes.html
    http://www.pinyin.info/rules/where.html

    Respect of these rules guarantee there's no ambiguity in the separation.

    Does not work with tone numbers as suffixed numeral (eg: ni3hao3)

    Useful as pre-processing for Google Translate's output.
    """
    def clean(t):
        'remove leading apostrophe'
        if "'" == t[0]:
            return t[1:]
        return t
    def separate_pinyin_sub(p):
        return clean(p.group("one"))+" "+clean(p.group("two"))
    #Run twice in case of overlapping sequences
    text =  pinyin_two_re.sub(separate_pinyin_sub, text)
    text =  pinyin_two_re.sub(separate_pinyin_sub, text)
    return text

#Demo
#print separate_pinyin(u"Yīlù píng'ān")