Using complex functions in widget

Hello everybody,

I am trying to use complex function in a widget.

I.e. make a simple calculation to have current with a sign (d.W1-drW1)/d.V1 but I get a NaN result (not a number).

I thought I was using incorrect syntax so I used the example in the Kb  just by dividing d.W1 /1000 and I get a NaN result too. But d.W1 displays correctly if used without operators.

Is there a problem in the complex function calculation?

Thanks

Fabio