WolfgangZillig wrote: > Hi, > > I'm quite new to numpy/scipy so please excuse if my problem is too obvious. > > example code: > > import numpy as n > print n.sin(n.pi) > print n.cos(n.pi/2.0) > > results in: > 1.22460635382e-016 > 6.12303176911e-017 > > I've expected something around 0. Can anybody explain what I am doing > wrong here?
Nothing. You are getting something around 0 to the limit of double-precision floating point. numpy.pi cannot be exactly π, but within about 1e-16 of it. That imprecision carries through the computations. -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion