c99 [ flag... ] file... –lm [ library... ] #include <math.h> double erfc(double x);
float erfcf(float x);
long double erfcl(long double x);
These function compute the complementary error function 1.0 − erf(x).
Upon successful completion, these functions return the value of the complementary error function.
If x is NaN, a NaN is returned.
If x is ±0, +1 is returned.
If x is −Inf, +2 is returned.
If x is +Inf, 0 is returned.
No errors are defined.
The erfc() function is provided because of the extreme loss of relative accuracy if erf(x) is called for large x and the result subtracted from 1.0.
See attributes(5) for descriptions of the following attributes: