Author tim.peters
Recipients davin, mark.dickinson, rhettinger, serhiy.storchaka, skrah, tim.peters
Date 2017-10-02.18:39:22
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Message-id <1506969563.08.0.213398074469.issue31630@psf.upfronthosting.co.za>
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If someone opens a bug report with OpenBSD, or just for us to get more info, it could be useful to have a larger universe of troublesome tan inputs to stare at.  So the attached tanny.py supplies them, testing all inputs within 100 ulps of math.pi/2 (or change N=100 to whatever you like).

There are no failures on my 64-bit Win10 3.6.1.

The "correct" answers are computed by using mpmath.tan() set to 200 mantissa bits, then rounding back to 53 bits.  These all match the results from my dirt-dumb decimal tan() rounded back, but it's better to trust a widely-used package.

Of course mpmath needs to be installed ("pip install mpmath" works fine):

    http://mpmath.org/

Nothing else is needed (while mpmath will exploit gmpy if it's installed, by default it sticks to pure Python code).
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Date User Action Args
2017-10-02 18:39:23tim.peterssetrecipients: + tim.peters, rhettinger, mark.dickinson, skrah, serhiy.storchaka, davin
2017-10-02 18:39:23tim.peterssetmessageid: <1506969563.08.0.213398074469.issue31630@psf.upfronthosting.co.za>
2017-10-02 18:39:23tim.peterslinkissue31630 messages
2017-10-02 18:39:22tim.peterscreate