[SciPy-Dev] request for testing: SciPy 0.7.2 RC1 + NumPy 1.4.1 RC1

Pauli Virtanen pav+sp@iki...
Wed Apr 7 12:13:30 CDT 2010

Thu, 08 Apr 2010 00:59:26 +0800., Ralf Gommers wrote:
> Thanks for testing. The failure is real, assert_equal(-0.0, 0.0) is
> supposed to fail. Now the question is whether the function or the test
> is wrong. Is cephes.nrdtrisd(0.5,0.5,0.5) supposed to return zero or
> minus zero?

Should be a positive zero, as the output is a standard deviation.

But it's ye olde Fortran code, and I suppose no thought has been paid on 
this sort of floating point corner cases. Also, the sign of zero probably 
doesn't even matter except in pathological situations -- so one could 
just accept the return value as it is and add an abs() to the test.

Pauli Virtanen

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