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Author serhiy.storchaka
Recipients brett.cannon, christian.heimes, mark.dickinson, serhiy.storchaka, zach.ware
Date 2017-03-12.09:00:27
SpamBayes Score -1.0
Marked as misclassified Yes
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There are accuracy issues with tgamma() and lgamma() on Windows. But less than on OS X.

FAIL: test_mtestfile (test.test_math.MathTests)
Traceback (most recent call last):
  File "C:\projects\cpython\lib\test\", line 1287, in test_mtestfile
    '\n  '.join(failures))
AssertionError: Failures in test_mtestfile:
  lgam0085: lgamma(-99.99999999999999): expected -331.85460524980596, got -331.86198661322277 (error = 0.00738 (129854318490 ulps); permitted error = 1e-15 or 5 ulps)
  gam0085: gamma(-99.99999999999999): expected 7.540083334884096e-145, got 7.484632144060724e-145 (error = 5.55e-147 (38979707393612 ulps); permitted error = 0 or 20 ulps)
  gam0124: gamma(-176.5): expected -1.196e-321, got 0.0 (error = 1.2e-321 (243 ulps); permitted error = 0 or 20 ulps)

Does this mean that we should not use libc implementations of tgamma() and lgamma() on Windows?
Date User Action Args
2017-03-12 09:00:27serhiy.storchakasetrecipients: + serhiy.storchaka, brett.cannon, mark.dickinson, christian.heimes, zach.ware
2017-03-12 09:00:27serhiy.storchakasetmessageid: <>
2017-03-12 09:00:27serhiy.storchakalinkissue26121 messages
2017-03-12 09:00:27serhiy.storchakacreate