"""Soundex algorithmThis program is part of "Dive Into Python", a free Python book forexperienced programmers.  Visit http://diveintopython.org/ for thelatest version."""__author__ = "Mark Pilgrim (mark@diveintopython.org)"__version__ = "$Revision: 1.2 $"__date__ = "$Date: 2004/05/06 21:36:36 $"__copyright__ = "Copyright (c) 2004 Mark Pilgrim"__license__ = "Python"import string, recharToSoundex = {"A": "9",                 "B": "1",                 "C": "2",                 "D": "3",                 "E": "9",                 "F": "1",                 "G": "2",                 "H": "9",                 "I": "9",                 "J": "2",                 "K": "2",                 "L": "4",                 "M": "5",                 "N": "5",                 "O": "9",                 "P": "1",                 "Q": "2",                 "R": "6",                 "S": "2",                 "T": "3",                 "U": "9",                 "V": "1",                 "W": "9",                 "X": "2",                 "Y": "9",                 "Z": "2"}isOnlyChars = re.compile('^[A-Za-z]+$').searchdef soundex(source):    "convert string to Soundex equivalent"    # Soundex requirements:    # source string must be at least 1 character    # and must consist entirely of letters    if not isOnlyChars(source):        return "0000"    # Soundex algorithm:    # 1. make first character uppercase    source = source[0].upper() + source[1:]        # 2. translate all other characters to Soundex digits    digits = source[0]    for s in source[1:]:        s = s.upper()        digits += charToSoundex[s]    # 3. remove consecutive duplicates    digits2 = digits[0]    for d in digits[1:]:        if digits2[-1] != d:            digits2 += d    # 4. remove all "9"s    digits3 = re.sub('9', '', digits2)        # 5. pad end with "0"s to 4 characters    while len(digits3) < 4:        digits3 += "0"            # 6. return first 4 characters    return digits3[:4]if __name__ == '__main__':    from timeit import Timer    names = ('Woo', 'Pilgrim', 'Flingjingwaller')    for name in names:        statement = "soundex('%s')" % name        t = Timer(statement, "from __main__ import soundex")        print name.ljust(15), soundex(name), min(t.repeat())