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cbrt, cbrtf, cbrtl

cube root function

Math library (libm, -lm)

#include <math.h>
double cbrt(double x);
float cbrtf(float x);
long double cbrtl(long double x);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

cbrt():

    _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
        || _XOPEN_SOURCE >= 500
        || /* Since glibc 2.19: */ _DEFAULT_SOURCE
        || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

cbrtf(), cbrtl():

    _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
        || /* Since glibc 2.19: */ _DEFAULT_SOURCE
        || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

These functions return the (real) cube root of x. This function cannot fail; every representable real value has a real cube root, and rounding it to a representable value never causes overflow nor underflow.

These functions return the cube root of x.

If x is +0, -0, positive infinity, negative infinity, or NaN, x is returned.

No errors occur.

For an explanation of the terms used in this section, see attributes(7).

Interface Attribute Value
cbrt (), cbrtf (), cbrtl () Thread safety MT-Safe

C11, POSIX.1-2008.

GNU, C99, POSIX.1-2001.

pow(3), sqrt(3)