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Math Library (libm, -lm)

#include <complex.h>

The
`clog()`,
`clogf()`,
and
`clogl()`
functions compute the complex natural logarithm of
z.
with a branch cut along the negative real axis .

The
`clog()`
function returns the complex natural logarithm value, in the
range of a strip mathematically unbounded along the real axis and in
the interval [-I* π , +I* π ] along the imaginary axis.
The function satisfies the relationship:
`clog(``conj(z)`)
=
`conj(``clog(z)`).

Argument | Return value | Comment |

-0 + I*0 | -∞ + I*π | Divide-by-zero exception |

raised | ||

+0 + I*0 | -∞ + I*0 | Divide by zero exception |

raised | ||

x + I*∞ | +∞ + I*π/2 | For finite x |

x + I*NaN | NaN + I*NaN | Optionally raises invalid |

floating-point exception | ||

for finite x | ||

-∞ + I*y | +∞ + I*π | For finite positive-signed y |

+∞ + I*y | +∞ + I*0 | For finite positive-signed y |

-∞ + I*∞ | +∞ + I*3π/4 | |

+∞ + I*∞ | +∞ + I*π/4 | |

±∞ + I*NaN | +∞ + I*NaN | |

NaN + I*y | NaN + I*NaN | Optionally raises invalid |

floating-point exception | ||

for finite y | ||

NaN + I*∞ | +∞ + I*NaN | |

NaN + I*NaN | NaN + I*NaN |

The
`clog()`,
`cexpf()`,
and
`clogl()`
functions conform to
ISO/IEC 9899:1999 ("ISO C99").

CLOG (3) | June 6, 2018 |

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