return substr( $str, 0, $length );
}
+/**
+ * Given an array of non-normalised probabilities, this function will select
+ * an element and return the appropriate key
+ *
+ * @param $weights array
+ *
+ * @return int|string
+ */
+function wfPickRandom( $weights ){
+ if ( !is_array( $weights ) || count( $weights ) == 0 ) {
+ return false;
+ }
+
+ $sum = array_sum( $weights );
+ if ( $sum == 0 ) {
+ # No loads on any of them
+ # In previous versions, this triggered an unweighted random selection,
+ # but this feature has been removed as of April 2006 to allow for strict
+ # separation of query groups.
+ return false;
+ }
+ $max = mt_getrandmax();
+ $rand = mt_rand( 0, $max ) / $max * $sum;
+
+ $sum = 0;
+ foreach ( $weights as $i => $w ) {
+ $sum += $w;
+ if ( $sum >= $rand ) {
+ break;
+ }
+ }
+ return $i;
+}
+
/**
* We want some things to be included as literal characters in our title URLs
* for prettiness, which urlencode encodes by default. According to RFC 1738,
* Given an array of non-normalised probabilities, this function will select
* an element and return the appropriate key
*
+ * @deprecated 1.21, use wfPickRandom()
+ *
* @param $weights array
*
* @return int
*/
function pickRandom( $weights ) {
- if ( !is_array( $weights ) || count( $weights ) == 0 ) {
- return false;
- }
-
- $sum = array_sum( $weights );
- if ( $sum == 0 ) {
- # No loads on any of them
- # In previous versions, this triggered an unweighted random selection,
- # but this feature has been removed as of April 2006 to allow for strict
- # separation of query groups.
- return false;
- }
- $max = mt_getrandmax();
- $rand = mt_rand( 0, $max ) / $max * $sum;
-
- $sum = 0;
- foreach ( $weights as $i => $w ) {
- $sum += $w;
- if ( $sum >= $rand ) {
- break;
- }
- }
- return $i;
+ return wfPickRandom( $weights );
}
/**