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author | nsz <nsz@port70.net> | 2012-03-22 14:54:47 +0100 |
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committer | nsz <nsz@port70.net> | 2012-03-22 14:54:47 +0100 |

commit | a4a0c91275788407763b1e5a9da17b777495ca85 (patch) | |

tree | 1c4e53cfe0c6b0ab80df621813acb74715e9ab3b /include/tgmath.h | |

parent | 2e0c1fed36be1f1435de79bfc7cdc34824cb5614 (diff) | |

download | musl-a4a0c91275788407763b1e5a9da17b777495ca85.tar.gz |

acos.s fix: use the formula acos(x) = atan2(sqrt(1-x),sqrt(1+x))

the old formula atan2(1,sqrt((1+x)/(1-x))) was faster but
could give nan result at x=1 when the rounding mode is
FE_DOWNWARD (so 1-1 == -0 and 2/-0 == -inf), the new formula
gives -0 at x=+-1 with downward rounding.

Diffstat (limited to 'include/tgmath.h')

0 files changed, 0 insertions, 0 deletions