gramps/gramps/gen/soundex.py

75 lines
2.4 KiB
Python

#
# Gramps - a GTK+/GNOME based genealogy program
#
# Copyright (C) 2000-2003 Donald N. Allingham
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
"""
Provide soundex calculation
"""
#-------------------------------------------------------------------------
#
# Standard python modules
#
#-------------------------------------------------------------------------
import unicodedata
#-------------------------------------------------------------------------
#
# constants
#
#-------------------------------------------------------------------------
IGNORE = "HW~!@#$%^&*()_+=-`[]\|;:'/?.,<>\" \t\f\v"
TABLE = bytes.maketrans(b'ABCDEFGIJKLMNOPQRSTUVXYZ',
b'012301202245501262301202')
#-------------------------------------------------------------------------
#
# soundex - returns the soundex value for the specified string
#
#-------------------------------------------------------------------------
def soundex(strval):
"Return the soundex value to a string argument."
strval = unicodedata.normalize(
'NFKD', str(strval.upper().strip())).encode('ASCII', 'ignore')
if not strval:
return "Z000"
strval = strval.decode('ASCII', 'ignore')
str2 = strval[0]
strval = strval.translate(TABLE)
if not strval:
return "Z000"
prev = strval[0]
for character in strval[1:]:
if character != prev and character != "0":
str2 = str2 + character
prev = character
# pad with zeros
str2 = str2+"0000"
return str2[:4]
#-------------------------------------------------------------------------
#
# compare - compares the soundex values of two strings
#
#-------------------------------------------------------------------------
def compare(str1, str2):
"1 if strings are close. 0 otherwise."
return soundex(str1) == soundex(str2)