issue using excel formula in transformation file

Hi,

I'm trying to remove invalid characters from CSV file for this, I'm using following formula but BPC is not accepting.

Is there something wrong?

Are there any better ideas (apart from using formula in transformation file) to remove invalid characters?

MATERIAL=*SUBSTITUTE ( *COL(3), "-", "")

MATERIAL dimension has a member of "testmat". if CSV file is trying to load a value of "test-mat", I would like to replace CSV file with "testmat".

So, Basically, I would like to remove all characters of "-" for dimension MATERIAL in my csv file with a blank character.

Also, are there any limitations on which excel formulas we can use in transformation file? Is there any online documention on this.

Appreciate any help.