creal(3) — Linux manual page

creal(3)                 Library Functions Manual                creal(3)

NAME         top

       creal, crealf, creall - get real part of a complex number

LIBRARY         top

       Math library (libm, -lm)

SYNOPSIS         top

       #include <complex.h>

       double creal(double complex z);
       float crealf(float complex z);
       long double creall(long double complex z);

DESCRIPTION         top

       These functions return the real part of the complex number z.

       One has:

           z = creal(z) + I * cimag(z)

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ creal(), crealf(), creall()          │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

VERSIONS         top

       GCC supports also __real__.  That is a GNU extension.

STANDARDS         top

       C11, POSIX.1-2008.

HISTORY         top

       glibc 2.1.  C99, POSIX.1-2001.

SEE ALSO         top

       cabs(3), cimag(3), complex(7)

COLOPHON         top

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Linux man-pages 6.15            2025-05-17                       creal(3)

Pages that refer to this page: cimag(3),  complex(7)

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