RegEx Question about Rule Based Filter

KNIME Analytics Platform
#1

Dear all,

by the help of the Rule Based Filter node I'm trying to get only rows where a specific string starts with exact three capital letters plus a dash ("-") followed by an arbitrary number of other characters (should be easy)

However, the following expression does not return any row although there are hundreds of possible candidates, e.g. BMW-4, REN-Clio, ...

$ItemsString$ MATCHES "^[A-Z]{3}\-"  => TRUE

(with "Include TRUE Matches" Option set).

I tried this also on a regex page (http://www.regexe.de/) and got the right results

Any ideas ? Thx in advance ...

 

#2

MATCHES tries to match the whole string and not only parts of it. Therefore you need to add ".*" at the back of your pattern.

#3

As I remember in prototype versions there were a method called CONTAINS with regular expressions, that would work for your attempt. With MATCHES, you should use something like the following (assuming no new lines):

$ItemsString$ MATCHES "^[A-Z]{3}\-.*"  => TRUE
#4

Thanks, thor, aborg - that worked !!!