VIVA calculator dnl&inl

Hi,

I try  expression below. It could not work.

dnl(abs(dac_out_DC) 0.625m  ?mode "auto"  ?crossType "rising" ?delay 0.0 ?method "end" ?units "lsb" ?nbsamples (256/VAR("dac_step")))

but it works when I use dnl(abs(dac_out_DC) 0.625m ?mode "auto" ?crossType "rising" ?delay 0.0 ?method "end" ?units "lsb" ?nbsamples 256).

The difference between these two expression is the "bnsamples" argument. Do you know why?

Thanks