2008/5/16 Stuart Brorson <[EMAIL PROTECTED]>: > Hi -- > > Sorry to be a pest with corner cases, but I found another one. > > In this case, if you try to take the arccos of numpy.inf in the > context of a complex array, you get a bogus return (IMO). Like this: > > In [147]: R = numpy.array([1, numpy.inf]) > > In [148]: numpy.arccos(R) > Warning: invalid value encountered in arccos > Out[148]: array([ 0., NaN]) > > In [149]: C = numpy.array([1+1j, numpy.inf]) > > In [150]: numpy.arccos(C) > Warning: invalid value encountered in arccos > Out[150]: array([ 0.90455689-1.06127506j, NaN -Infj]) > > The arccos(numpy.inf) in the context of a real array is OK, but taking > arcocs(numpy.inf) in the context of a complex array should return > NaN + NaNj, IMO. > > Thoughts?
Is this so bad? lim x->inf arccos(x) = -j inf Granted this is only when x approaches infinity along the positive real axis... Anne _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion