Combine three fields into one field

[bhaveshp90]

Hello, 

I have a table with Cost_Area  field which has values as:

I am trying to combine multiple fields ('CONT HDWR', 'CONT RESALE', 'CONTROLS ENG') in load script as one field  (named "Controls Eng"). So, my resultant column "Controls Eng" would be a list having values like 'CONT HDWR', 'CONT RESALE', 'CONTROLS ENG' and not the other fields.  

How can I do this? 

attach is the file for reference

[dplr-rn]

not sure exactly what you mean. i see you are doing
[Cost Area]='CONT HDWR' , 'Cont Hdwr' why not change 'Controls Eng'
also if you use a applymap instead of the nested if it maybe faster