ERFC(3) | Linux Programmer's Manual | ERFC(3) |
NAME
erfc, erfcf, erfcl - complementary error functionSYNOPSIS
#include<math.h>
double erfc(double x);
float erfcf(float x);
long double erfcl(long double x);
Link with -lm.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
erfc():
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
or
cc -std=c99
erfcf(), erfcl():
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600|| _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
or
cc -std=c99
DESCRIPTION
The erfc() function returns the complementary error function of x, that is, 1.0 - erf(x).RETURN VALUE
On success, these functions return the complementary error function of x, a value in the range [0,2].ERRORS
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.The following errors can occur:
- Range error: result underflow (result is subnormal)
- An underflow floating-point exception ( FE_UNDERFLOW) is raised.
These functions do not set errno.
CONFORMING TO
C99, POSIX.1-2001. The variant returning double also conforms to SVr4, 4.3BSD.NOTES
The erfc() functions are provided to avoid the loss accuracy that would occur for the calculation 1-erf(x) for large values of x (for which the value of erf(x) approaches 1).SEE ALSO
cerf(3), erf(3), exp(3)COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.2010-09-20 | GNU |