Calculate similarity between 2 strings

Hello,

In my search help, I need to rank my result according to the similarity of my input parameter.

Ex : Input parameter = TOTO

My result :

1- TOTO

2- TOT

3- TOTO NEW

Do you know a function or a method to calculate the similarity between 2 strings?

I implemented this levenshtein algo [http://en.wikibooks.org/wiki/Algorithm_Implementation/Strings/Levenshtein_distance#Abap] but, the result is not appropriate.

Thanks in advance.

Best regards,

Xavier.