third-party-mirror / mingw-w64 / 063fb9eda93b76f6715cee4894a2dc19323f13bd / . / mingw-w64-crt / math / arm-common / acosh.c

/** | |

* This file has no copyright assigned and is placed in the Public Domain. | |

* This file is part of the mingw-w64 runtime package. | |

* No warranty is given; refer to the file DISCLAIMER.PD within this package. | |

*/ | |

#include <math.h> | |

double acosh(double x) | |

{ | |

if (x < 1.0) | |

return NAN; | |

if (isinf(x*x)) | |

return log(2) + log(x); | |

return log(x + sqrt(x*x - 1)); | |

} |