| Pré. | Proc. |
erfc
Complementary error function.SYNOPSIS:
double x, y, erfc();
y = erfc(x);
DESCRIPTION:
1 - erf(x) =
inf.
-
2 | | 2
erfc(x) = -------- | exp(- t) dt
sqrt(pi) | |
-
x
For small x, erfc(x) = 1 - erf(x); otherwise rational approximations are computed.
A special function expx2.c is used to suppress error amplification in computing exp(-x^2).
ACCURACY:
Relative error:
arithmetic domain # trials peak rms
IEEE 0,26.6417 30000 1.3e-15 2.2e-16
ERROR MESSAGES:
message condition value returned
underflow x > 9.231948545 (DEC) 0.0