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| author | nsz <nsz@port70.net> | 2012-05-05 01:11:56 +0200 |
|---|---|---|
| committer | nsz <nsz@port70.net> | 2012-05-05 01:11:56 +0200 |
| commit | f697d66b81912af59128ac1b96bc0e2a4514b758 (patch) | |
| tree | 32433a4df7d33f692afa2ff6e759fa1c5870b8f0 /include/string.h | |
| parent | db4096c5f2ffb15e52015004ab5a900b820c6683 (diff) | |
| download | musl-f697d66b81912af59128ac1b96bc0e2a4514b758.tar.gz musl-f697d66b81912af59128ac1b96bc0e2a4514b758.tar.xz musl-f697d66b81912af59128ac1b96bc0e2a4514b758.zip | |
math: change the formula used for acos.s
old: 2*atan2(sqrt(1-x),sqrt(1+x)) new: atan2(fabs(sqrt((1-x)*(1+x))),x) improvements: * all edge cases are fixed (sign of zero in downward rounding) * a bit faster (here a single call is about 131ns vs 162ns) * a bit more precise (at most 1ulp error on 1M uniform random samples in [0,1), the old formula gave some 2ulp errors as well)
Diffstat (limited to 'include/string.h')
0 files changed, 0 insertions, 0 deletions