Help excluding all of an expression except for two specific expressions

hello,

I've been using knime to play around with my company's SQL database and I'm looking to ommit everything except a certain expression but can't for the life of me figure out how to go about this. The format of the colum in question is "WXRE3257903_R1" etc. or it could be "RTSO283746_F1". so what i'm looking to do is to assign a boolean value to "_R1" and "_F1". to do this, i need to find a way to filter out all of the rest of the data, which can be of different lengths and formats. the only common factor is the _F and the _R.

 

Any help would be greatly appreciated,

Thanks.

In terms of a regex expression, how about something like

[A-Z]{4}[0-9]{6}_(R|F)[0-9]

 

simon.