CACOSH(3) BSD Library Functions Manual CACOSH(3)

NAME
     ccaaccoosshh - complex inverse hyperbolic cosine function

SYNOPSIS
     double complex
     ccaaccoosshh(double complex z);

     long double complex
     ccaaccoosshhll(long double complex z);

     float complex
     ccaaccoosshhff(float complex z);

DESCRIPTION
     ccaaccoosshh(z) computes the inverse hyperbolic cosine of the complex floating-
     point number z, with a branch cut on the interval [-inf, 1] along the
     real axis.

     ccaaccoosshh() returns values in a half-strip of the complex plane with posi-
     tive real part and imaginary part in the interval [-Pi, Pi].

     For all complex floating point numbers z, cacosh(conj(z)) =
     conj(cacosh(z)).

SSPPEECCIIAALL VVAALLUUEESS
     The conjugate symmetry of cacosh() is used to abbreviate the specifica-
     tion of special values.

     ccaaccoosshh(+-0 + 0i) returns 0 + Pi/2 i.

     ccaaccoosshh(x + inf i) returns inf + Pi/2 i, for finite x.

     ccaaccoosshh(x + NaN i) returns NaN + NaN i, for finite nonzero x.

     ccaaccoosshh(-inf + yi) returns inf + Pi i, for finite positive-signed y.

     ccaaccoosshh(inf + yi) returns inf + 0i, for finite positive-signed y.

     ccaaccoosshh(-inf + inf i) returns inf + 3Pi/4 i.

     ccaaccoosshh(inf + inf i) returns inf + Pi/4 i.

     ccaaccoosshh(+-inf + NaN i) returns inf + NaN i.

     ccaaccoosshh(NaN + yi) returns NaN + NaN i, for finite y.

     ccaaccoosshh(NaN + inf i) returns inf + NaN i.

     ccaaccoosshh(NaN + NaN i) returns NaN + NaN i.

NNOOTTEESS
SEE ALSO
     ccosh(3) complex(3)

STANDARDS     The ccaaccoosshh() function conforms to ISO/IEC 9899:1999(E).

4th Berkeley Distribution      November 9, 2006      4th Berkeley Distribution