what about the percentage how much accurate the result returned??
I'm not sure what kind of keywords or text you're searching, but here's the algorithm i used a while back, for plain-text search:
given: $query $text
/*
curve() maps values between 0 and 1 to.. a curve:
0% -> 0%
25% -> 43%
50% -> 75%
75% -> 93%
100% -> 100%
*/
function curve($x){
$x = 1 - $x;
$x = $x * $x;
return 1 - $x;
}/*
given a number between 0 and +INFINITY,
strength returns a value between 0 and 1 (0% and 100%)
the higher $n is, the closer to 1 the result.
0 -> 0% 6 -> 85.7%
1 -> 50% 7 -> 87.5%
2 -> 66.6% 8 -> 88.8%
3 -> 75% 9 -> 90%
4 -> 80% 19 -> 95%
5 -> 83.3% 100 -> 99%
*/
function strength($x){
return ($x / ($x + 1))
}$count = 0
$keywords = (split $query into array of whole words)
for (each word in $query) {
$n = (number of times $word found in $text);
// add the size of $word to $count, or more depending on $n
$count += (length of $word) * (1 + strength($n));
}
$score = ($count + $count) / (length of $query + length of $text );
$score = curve($score); // repeat a few times if needed, to get decent scores
and there you have it.
------------------------------------- mikon
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