Re: [Bug-gsl] [bug #47347] Complex tangent failure for -1000i

[Patrick Alken]

Thanks for your work on this, your patch works very nicely. I've added
it to the git. I'm still working through your other patches.

On 09/11/2016 10:51 PM, Yu Liu wrote:
> Follow-up Comment #1, bug #47347 (project gsl):
>
> Please see test_tan.c for trouble shooting process and gsl_complex_tan.diff
> for a proposed fix.
> 1. This proposed fixed is based on 7141c7adb8100207ef01ff87a94d5179103fcebc
> which add a branch in  gsl_complex_tanh to handle a similar issue. In this
> commit, tanh was modified to have a separate branch to handle large real part
> in input. This is what gsl_complex_tan.diff is doing in essense. In
> test_tan.c, this idea is implemented in `gsl_complex_tan_2` for testing
> purposes.
> 2. glibc implementation
> (https://github.com/lattera/glibc/blob/a2f34833b1042d5d8eeb263b4cf4caaea138c4ad/math/s_ctan.c)
> converts everything to exponential when the imagineary part is big. Is this a
> better implementation?
>
>
>
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