How to replace a certain column value by MISSING_NOMINAL ?

alain

I have an Excel file that contains the word NULL in certain cells to indicate a missing value.

I want to replace that word by MISSING_NOMINAL, so RapidMiner can interprete it correctly as a missing value.

What operator can do this?

kypexin

Hi @alain

I want to replace that word by MISSING_NOMINAL, so RapidMiner can interprete it correctly as a missing value

The solutions offered here are replacing one string with another, but is that what you really need? 
There's also an operator called DECLARE MISSING VALUE which will actually replace specified values with real missing values (will be displayed as ?) and they will be interpreted as such by RapidMiner. 

varunm1

Hi @alain

If you are looking to replace the word NULL. You can use the Replace operator. Select the attribute filter type "single" and then select the relevant attribute (Column). If this NULL is present in all columns then you can select "all" in attribute filter type.   After that, you can specify NULL in "replace what" and the value you want MISSING_NOMINAL in "replace by". 

Hope this helps.

MartinLiebig

Hi,

alternativly you can use Generate Attributes and use an equation like this:

if(Wind==false,MISSING_NOMINAL,Wind)

BR,

Martin