Sambo <[EMAIL PROTECTED]> wrote: > I have the following module: > ------------------------------- > import math > > def ac_add_a_ph( amp1, ph1, amp2, ph2 ): > > amp3 = 0.0 > ph3 = 0.0 > ac1 = ( 0, 0j ) > ac2 = ( 0, 0j ) > ac3 = ( 0, 0j )
You're defining ac1, ac2, ac3 as tuples, each with two items. That's silly: remove these three useless and confusing lines (the first two are prety silly too). No damage, but, avoidable extra confusion. > ac1 = complex( amp1 * math.cos( math.radians( ph1 ) ), amp1 * \ math.sin( math.radians( ph1 ) ) ) > ac2 = complex( amp2 * math.cos( math.radians( ph2 ) ), amp2 * \ math.sin( math.radians( ph2 ) ) ) > ac3 = ac1 + ac2 > amp3 = math.abs( ac3 ) > ph3 = math.atan( ac3.imag / ac3.real ) > return [amp3, ph3] > -------------------------------------- > when I import it (electronics) in python.exe in windows2000 and > try to use it, it croaks. ??? > > >>> import math > >>> import electronics > >>> print electronics.ac_add_a_ph( 10, 0 , 6 , 45 ) > Traceback (most recent call last): > File "<stdin>", line 1, in ? > File "f:\devel\python\electronics.py", line 10, in ac_add_a_ph > ac1 = complex( amp1 * math.cos( math.radians( ph1 ) ), amp1 * \ math.sin( math > .radians( ph1 ) ) ) [[some lines split to respect NNTP's constraint on 80-char lines]] > NameError: global name 'cos' is not defined > >>> > > > global?? huh? Weird -- I can't reproduce this; it's the kind of symptom you get when mistakenly using a comma instead of a dot, for example, but I don't see that error in your code. What I _do_ see is an "AttributeError: 'module' object has no attribute 'abs'" on the amp3 assignment -- of course, because that's indeed the fact (abs is a builtin, not a member to module math). Most likely, you got a bit confused and didn't copy-and-paste exactly what was going on. > what does abs stand for? why is that not absolute value? hmmm. abs does stand for absolute-value. > Hmm, complex numbers, cool I don't even have any idea where C > stands on this. C has no stand on complex numbers. Alex -- http://mail.python.org/mailman/listinfo/python-list
