Argl. My fault. As often like on StackO, I have discovered the answer just after posting the question.

After using the debugger, the non-numeric value is on the left side of the expression (it is coming from a sql select and can also be null/empty in some circumstances).

The best programs are the ones written when the programmer is supposed to be working on something else. - Melinda Varian

In reply to Re: Argument "" isn't numeric in division (/) by seki
in thread Argument "" isn't numeric in division (/) by seki

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