Add new column to DataView

Hi, can I add a new column to a DataView and give it a value according to another column value?

Example:
I have a DataView where I create a new column called "Color". I have the column "Number" and if "Number" is greater than 0 I add "Green" to "Color", if "Number" is lower than 0 I add "Red" to the "Color".

Any help please? thanks