Getting absolute value

Hi All,

Need your inputs here. My requirement is like I need to to display a block based on one logic

If abs(a-b) = plus or minus 10, the value should appear..

There is column a and column b in one block. If the difference between them is plus or minus 10, then I have to show else hide the block.

How do we achieve this in Webi. Backend is BW

Your inputs on this would help me.

Thanks,

Harsha