1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
|
/*
[Header: soundexmodule.c,v 1.2 95/05/02 15:40:45 dwwillia Exp ]
Perform soundex comparisons on strings.
Soundex is an algorithm that hashes English strings into numerical value.
Strings that sound the same are hashed to the same value. This allows
for non-literal string matching.
From: David Wayne Williams <dwwillia@iucf.indiana.edu>
Apr 29 1996 - added get_soundex method that returns the soundex of a
string (chrish@qnx.com)
May 2 1996 - added doc strings (chrish@qnx.com)
*/
#include <string.h>
#include <ctype.h>
#include "Python.h"
static char soundex_module__doc__[] =
"Perform Soundex comparisons on strings, allowing non-literal matching.";
static void soundex_hash(char *str, char *result)
{
char *sptr = str; /* pointer into str */
char *rptr = result; /* pointer into result */
if(*str == '\0')
{
strcpy(result,"000000");
return;
}
/* Preserve the first character of the input string.
*/
*(rptr++) = toupper(*(sptr++));
/* Translate the rest of the input string into result. The following
transformations are used:
1) All vowels, W, and H, are skipped.
2) BFPV = 1
CGJKQSXZ = 2
DT = 3
L = 4
MN = 5
R = 6
3) Only translate the first of adjacent equal translations. I.E.
remove duplicate digits.
*/
for(;(rptr - result) < 6 && *sptr != '\0';sptr++)
{
switch (toupper(*sptr))
{
case 'W':
case 'H':
case 'A':
case 'I':
case 'O':
case 'U':
case 'Y':
break;
case 'B':
case 'F':
case 'P':
case 'V':
if(*(rptr - 1) != '1')
*(rptr++) = '1';
break;
case 'C':
case 'G':
case 'J':
case 'K':
case 'Q':
case 'S':
case 'X':
case 'Z':
if(*(rptr - 1) != '2')
*(rptr++) = '2';
break;
case 'D':
case 'T':
if(*(rptr - 1) != '3')
*(rptr++) = '3';
break;
case 'L':
if(*(rptr - 1) != '4')
*(rptr++) = '4';
break;
case 'M':
case 'N':
if(*(rptr - 1) != '5')
*(rptr++) = '5';
break;
case 'R':
if(*(rptr -1) != '6')
*(rptr++) = '6';
default:
break;
}
}
/* Pad 0's on right side of string out to 6 characters.
*/
for(; rptr < result + 6; rptr++)
*rptr = '0';
/* Terminate the result string.
*/
*(result + 6) = '\0';
}
/* Return the actual soundex value. */
/* Added by Chris Herborth (chrish@qnx.com) */
static char soundex_get_soundex__doc__[] =
"Return the (English) Soundex hash value for a string.";
static PyObject *
get_soundex(PyObject *self, PyObject *args)
{
char *str;
char sdx[7];
if(!PyArg_ParseTuple( args, "s", &str))
return NULL;
soundex_hash(str, sdx);
return PyString_FromString(sdx);
}
static char soundex_sound_similar__doc__[] =
"Compare two strings to see if they sound similar (English).";
static PyObject *
sound_similar(PyObject *self, PyObject *args)
{
char *str1, *str2;
char res1[7], res2[7];
if(!PyArg_ParseTuple(args, "ss", &str1, &str2))
return NULL;
soundex_hash(str1, res1);
soundex_hash(str2, res2);
if(!strcmp(res1,res2))
return Py_BuildValue("i",1);
else
return Py_BuildValue("i",0);
}
/* Python Method Table.
*/
static PyMethodDef SoundexMethods[] =
{
{"sound_similar", sound_similar, 1, soundex_sound_similar__doc__},
{"get_soundex", get_soundex, 1, soundex_get_soundex__doc__},
{NULL, NULL } /* sentinel */
};
/* Register the method table.
*/
void
initsoundex()
{
(void) Py_InitModule4("soundex",
SoundexMethods,
soundex_module__doc__,
(PyObject *)NULL,
PYTHON_API_VERSION);
}
|
