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
|
namespace DSALib.Auxiliary {
public class SpellCorrect {
public const double ErrorThreshold = 1 / 3.0;
private const double Match = 3.0;
private const double Gap = -1.5;
private const double Mismatch = -2.0;
public static double Compare(string s, string q) {
s = s.ToLower();
q = q.ToLower();
int i, j;
var matrix = new double[s.Length + 1, q.Length + 1];
var max = 0.0;
matrix[0, 0] = 0.0;
for (i = 1; i < s.Length; i++)
matrix[i, 0] = i * Gap;
for (i = 1; i < q.Length; i++) matrix[0, i] = 0.0;
for (i = 1; i <= s.Length; i++)
for (j = 1; j <= q.Length; j++) {
var decay = j / (s.Length * 1000.0);
var add = s[i - 1] == q[j - 1] ? Match - decay : Mismatch;
var score = matrix[i - 1, j - 1] + add;
if (score < matrix[i - 1, j] + Gap) score = matrix[i - 1, j] + Gap;
if (score < matrix[i, j - 1] + Gap) score = matrix[i, j - 1] + Gap;
if (i > 1 && j > 1)
if (s[i - 1] == q[j - 2] && s[i - 2] == q[j - 1]) {
add = 3 / 2.0 * Match - decay;
if (score < matrix[i - 2, j - 2] + add) score = matrix[i - 2, j - 2] + add;
}
if (max < score && i == s.Length) max = score;
matrix[i, j] = score;
}
return max;
}
public static bool IsMatch(string s1, string s2) {
var score = Compare(s1, s2);
return score > ErrorThreshold * s1.Length;
}
}
}
|