On Fri, 22 Sep 2000, Masahiro Tanaka wrote: > > A cautionary tale for users of dynamical languages such as Ruby: > > > > I had the constant definitions above in a unit test file but the test > > cases kept failing no matter what I did. The problem was that I included > > the NArray extension which in turn included Complex which redefined > > Math.log so that it returned the correct complex number instead of > > -Infinity above. Makes you think before changing the behavior of methods > > in the standard distr... (and yes, I now know complex aliases Math.log to > > Math.log!) > > I do not know how you use the NArray extension, but > to avoid other readers confuse, I note: > > * NArray function module is NMath, not Math. > * NMath.log(-1) returns -Infinity. > > % irb -r narray > irb(main):001:0> NMath.log(-1) > -Infinity > irb(main):002:0> NMath.log(-1.0+0.im) > Complex(0.0, 3.141592654) > I was using NArray for some other stuff but not for getting INF. So: $ irb irb(main):001:0> Math.log(-1) -Infinity irb(main):002:0> require 'narray' true irb(main):003:0> Math.log(-1) Complex(0.0, 3.141592654) irb(main):004:0> Regards, Robert