CACOS, CACOSF, CACOSL - reference manual online

Complex arc cosine.

CACOS(3)                            Linux Programmer's Manual                            CACOS(3)

NAME cacos, cacosf, cacosl - complex arc cosine
SYNOPSIS #include <complex.h> double complex cacos(double complex z); float complex cacosf(float complex z); long double complex cacosl(long double complex z); Link with -lm.
DESCRIPTION These functions calculate the complex arc cosine of z. If y = cacos(z), then z = ccos(y). The real part of y is chosen in the interval [0,pi]. One has: cacos(z) = -i * clog(z + i * csqrt(1 - z * z))
VERSIONS These functions first appeared in glibc in version 2.1.
ATTRIBUTES For an explanation of the terms used in this section, see attributes(7). ┌─────────────────────────────┬───────────────┬─────────┐ │Interface │ Attribute │ Value │ ├─────────────────────────────┼───────────────┼─────────┤ │cacos(), cacosf(), cacosl() │ Thread safety │ MT-Safe │ └─────────────────────────────┴───────────────┴─────────┘
CONFORMING TO C99, POSIX.1-2001, POSIX.1-2008.
EXAMPLE /* Link with "-lm" */ #include <complex.h> #include <stdlib.h> #include <unistd.h> #include <stdio.h> int main(int argc, char *argv[]) { double complex z, c, f; double complex i = I; if (argc != 3) { fprintf(stderr, "Usage: %s <real> <imag>\n", argv[0]); exit(EXIT_FAILURE); } z = atof(argv[1]) + atof(argv[2]) * I; c = cacos(z); printf("cacos() = %6.3f %6.3f*i\n", creal(c), cimag(c)); f = -i * clog(z + i * csqrt(1 - z * z)); printf("formula = %6.3f %6.3f*i\n", creal(f), cimag(f)); exit(EXIT_SUCCESS); }
SEE ALSO ccos(3), clog(3), complex(7)
COLOPHON This page is part of release 4.04 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at
2015-04-19 CACOS(3)
This manual Reference Other manuals
cacos(3) referred by acos(3) | ccos(3) | complex(7)
refer to attributes(7) | ccos(3) | clog(3) | complex(7)