erfc, erfcf, erfcl - complementary error function
#include <math.h> double erfc(double x); float erfcf(float x); long double erfcl(long double x);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L || /* Since glibc 2.19: */ _DEFAULT_SOURCE || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
These functions return the complementary error function of
x, that is, 1.0 - erf(x).
On success, these functions return the complementary error function
x, a value in the range [0,2].
x is a NaN, a NaN is returned.
x is +0 or -0, 1 is returned.
x is positive infinity, +0 is returned.
x is negative infinity, +2 is returned.
If the function result underflows and produces an unrepresentable value, the return value is 0.0.
If the function result underflows but produces a representable (i.e., subnormal) value, that value is returned, and a range error occurs.
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
An underflow floating-point exception (FE_UNDERFLOW) is raised.
These functions do not set
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning
double also conforms to SVr4,
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