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
|
/*
[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>
*/
#include <string.h>
#include <ctype.h>
#include "Python.h"
void soundex_hash(char *str, char *result)
{
char *sptr = str; /* pointer into str */
char *rptr = result; /* pointer into result */
if(*str == NULL)
{
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 vowles, W, and H, are skipped.
2) BFPV = 1
CGJKQSXZ = 2
DT = 3
L = 4
MN = 5
3) Only translate the first of adjacent equal translations. I.E.
remove duplicate digits.
*/
for(;(rptr - result) < 6 && *sptr != NULL;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;
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) = NULL;
}
static PyObject *
sound_similar(PyObject *self, PyObject *args)
{
char *str1, *str2;
int return_value;
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},
{NULL, NULL } /* sentinel */
};
/* Register the method table.
*/
void
initsoundex()
{
(void) Py_InitModule("soundex",SoundexMethods);
}
|
