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CACOS(3) | Linux Programmer's Manual | CACOS(3) |
NAME¶
cacos, cacosf, cacosl - complex arc cosineSYNOPSIS¶
#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 4.10 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 https://www.kernel.org/doc/man-pages/.2015-04-19 |