Fix exponential() #226
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Fix exponential() #226
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Fix various issues in exponential() like: - ** 1000 needing over 1600 iterations - ** -1000 yielding a large positive number - ** 2000 not converging after 2570 iterations The fix involves scaling down x to [0.5, 1) and expamding the Taylor series with increased precision. The iteration count is now <= 17 with up to 47 multiplications to scale the result in the worst case.
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Fix various issues in exponential() like:
The fix involves scaling down x to [0.5, 1) and expanding the Taylor series with increased precision.
The iteration count is now <= 17 with up to 47 multiplications to scale the result in the worst case.
The results are almost always properly rounded, and off by 1 ulp in the worst case.
I'd like to add a test for this, but because of #225, there is no really clean way to do it.