Empty String to Missing Value

Manipulating "Missing Values" is easy to do in KNIME, but  I would like to convert an empty String into a missing value.  Is there an easy way to do this?



I think this is possible with the string replacer node now to manipulate empty strings



I beleive Simon meant String Manipulator node's toNull function. Another option might be a Java Snippet node returning nulls for isEmpty() arguments.

I did actually mean string replacer node, new feature to knime 2.8. 

But of course you can use string manipulator node too. 


Hi Simon,

   Could you provide an example for the arguments how to specify missing value? I see no way on the UI or in the documentation to set as missing value.

Thanks, gabor

It seems you're right, I misread the log file for 2.8

you can now replace empty strings for anything now, except for missing values! Which is great news as the string replacer was most limited without tis option.

so long and short of it is it looks like string manipulator is the main option here.


Hi Macca,

the Knode “String Manipulation” works well by using the command

toNull(regexReplace($ColumnName$, “”, “”))