On Sun, 30 Jan 2005, Brandon wrote: > I'm trying to write a program they may involve needing to divide 1 by > another number. In the program below when I use 4 for the diameter of > the bore, and 1 for the diameter of the rod, and 60 for the PSI, the > force should be 706.8 . However the program keeps giving me 0 for > "rodarea".
In addition to the real division issue that's already been pointed out (simplest fix is to divide by 4.0 instead of 4 to avoid this), you've got another problem: > area = (bore**2/4)*PI > rodarea = (rod**2/4)*PI Both of your formulas above are the same. So, where bore = rod, as in your example where they're both equal to 1, area and rodarea are both going to evaluate to the same value: >>> bore = 1 >>> rod = 1 >>> PI = 3.14 >>> area = (bore**2/4.0)*PI >>> rodarea = (rod**2/4.0)*PI >>> area 0.78500000000000003 >>> rodarea 0.78500000000000003 Now, look at your nest line: > force = (area-rodarea)*psi since area is equal to rodarea when bore is equal to rod, area-rodarea will always = 0, and force will equal 0, too, not 706.8 as you're expecting. This isn't just a matter of when you use 1, it's true whenever you use equal values for rod and bore. _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
