Category : Miscellaneous Language Source Code
Archive   : QTAWKU42.ZIP
Filename : SOUNDIX.EXP

# SOUNDIX Version 1.0

{
# for ( i = 1 ; i <= NF ; i++ ) print soundex($i);
for ( i = 1 ; i <= NF ; i++ ) printf(" Result: %s ==> %s\n",$i,soundex($i));
}

# SOUNDIX Version 1.0
#
# This program takes a character string such as a person's last
# name and translates it to a sound index. This index can then be
# used by an application to perform phonetic (i.e. 'sounds-like')
# search. Algorithm found in D. Knuth, "Art of Computer Programming",
# Vol. 3, Page 391-392
#
# Rules:
# =====
#
# 1) Retain the first letter of the name and drop all occurances of
# a, e, h, i, o, u, w, and y in other positions
# 2) assign the following numbers to the remaining letters after the first
# bfpv ==> 1
# cgjkqsxz ==> 2
# dt ==> 3
# l ==> 4
# mn ==> 5
# r ==> 6
#
# 3) if two or more letters with the same code were adjacent in the original
# string (before step 1), omit all but the first
#
# 4) convert to the form "letter, digit, digit, digit" by adding trailing
# zeros (if there are less than three digits) by dropping rightmost
# digits (if there are more than three).
#
#
# Logic:
# =====
#
# 1) Uppercase the string
# 2) Use suffix to first letter
# 3) Change the following letters:
# R to 6
# M,N to 5
# L to 4
# D,T to 3
# C,G,J,K,Q,S,X,Z to 2
# B,F,P,V to 1
# AEIOUYHW to 0
# anything else to 0
# 4) Remove all adjacent duplicates
# 5) Remove all zeros
#
# Example: (  and  marks duplicates which are deleted )
# =======
# 
# McClowry --> 52240060 --> 5246 --> M246
# McLorey --> 5240600 --> 5246 --> M246
# 
# Schiller --> 22004406 --> 246 --> S460
# Shilar --> 200406 --> 246 --> S460
#
# Rosen --> 60205 --> 625 --> R250
# Rozin --> 60205 --> 625 --> R250
#
# Moynihan --> 50050005 --> 555 --> M550
# Monnihan --> 50550005 --> 555 --> M550
# 
# Abete --> 01030 --> 013 --> A130
# Abadey --> 010300 --> 013 --> A130
#
#
function soundex(str) {
local ldl;
local t_from = "|@#$%:;&*()_-+=![]'{}?/<>.~`^1234567890AEIOUYHWBFPVCGJKQSXZDTLMNR\\";
local t_to = "000000000000000000000000000000000007000000000001111222222223345560";

str = strupr(str);
ldl = substr(str,1,1); # rule 1
gsub(/^[AEIOUYH]/,"7",str); # reserve leading "AEIOUYH"
str = stran(str,t_to,t_from); # rule 2

gsub(/11+/,"1",str); # replace duplicate 1's with single 1 rule 3
gsub(/22+/,"2",str); # replace duplicate 2's with single 2 rule 3
gsub(/33+/,"3",str); # replace duplicate 3's with single 3 rule 3
gsub(/44+/,"4",str); # replace duplicate 4's with single 4 rule 3
gsub(/55+/,"5",str); # replace duplicate 5's with single 5 rule 3
gsub(/66+/,"6",str); # replace duplicate 6's with single 6 rule 3
gsub(/0+/,"",str); # delete internal 0's, rule 1

str = ldl substr(str,2); # glue leading character back on front
if ( (ldl = length(str)) < 4 ) {
switch ( ldl ) {
case 1:
str ï= "000";
break;
case 2:
str ï= "00";
break;
case 3:
str ï= "0";
break;
}
} else if ( ldl > 4 ) str = substr(str,1,4);

return str;
}