Rewritten, maybe -- but the algorithm has some obvious
optimisations which can be done, for example...
function text__soundex( $text ) {
$k = ' 123 12 22455 12623 1 2 2';
$nl = strlen( $tN = strtoupper( $text ) );
$p = trim( $k{ ord( $tS = $tN{0} ) - 65 } );
for( $n = 1; $n < $nl; ++$n )
if( ( $l = trim( $k{ ord( $tN{ $n } ) - 65 } ) ) != $p )
$tS .= ( $p = $l );
return substr( $tS . '000', 0, 4 );
}
// Notes:
// $k is the $key, essentially $SoundKey inverted
// $tN is the uppercase of the text to be optimised
// $tS is the partaully generated output
// $l is the current letter, $p the previous
// $n and $nl are iteration indicies
// 65 is ord('A'), precalculated for speed
// none ascii letters are not supported
// watch the brackets, quite a mixture here
(Code has suffered only basic tests, though it appears to
match the output of PHP's soundex(), speed untested --
though this should be /much/ faster than a4_perfect's
rewrite due to the removal of most loops and compares.)
C
2005-09-13
