Best way to change values in multiple columns in KNIME

KNIME Analytics Platform
1

Hi,

I'm wondering if there is any way to iterate over multiple columns in KNIME using a Java snippet of some sort.  What I'm doing right now involves a Column List Loop Start, Column Rename, Java Snippet, Column Rename, and Loop End.  This gets the job done, but it seems unwieldy.  Is there a way to do this directly using Java?

An example of the kind of thing I'm doing is mapping "true/false" values to 1.0 or 0.0 for a large number of String columns for learners which expect features to be of type Double.  Another example would be to map null values to -1.0 for a large number of columns of type Double.

Thanks!

 

 

2

Have you tried using the Unpivot node? In the cases that you describe I believe that Unpifot > Rule Engine > Pivot node sequence should do the trick.