hi
command line???
a formula would work better.
you are dividing some cell by another cell that has a zero value. lets say
the first cell is a1 and the second is b1.
in a1..
=if(b1=0,0,A1/B1)
this way if b1 is zero the math will not take place. if it is not zero, the
formula will calculate.
Regards
FSt1