Hi

I've gone through the forums and also looked at all the workarounds suggested, but still have had no luck for my case.

I have a numeric array (so 5 items, with dropdown numbers from 1 to 5 across two columns). Is there anyway to force only one number to be used per column? I tried working with the unique(Self) validation, but that's not working at expected.

Am I missing something obvious?

Thanks!

If, for example, your X-scale codes are "A1" and A2", you can use this as the question validation equation:


Sample question attached:

Oh wow! This works great. Thank you!