|ERFC(3)||Linux Programmer's Manual||ERFC(3)|
NAMEerfc, erfcf, erfcl - complementary error function
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)):
DESCRIPTIONThe erfc() function returns the complementary error function of x, that is, 1.0 - erf(x).
RETURN VALUEOn success, these functions return the complementary error function of x, a value in the range [0,2].
ERRORSSee 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 TOC99, POSIX.1-2001. The variant returning double also conforms to SVr4, 4.3BSD.
NOTESThe 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 ALSOcerf(3), erf(3), exp(3)
COLOPHONThis 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/.