erf(3F)
NAME
erf, erfc − error function and complementary error function
SYNOPSIS
double precision function erf (x)
double precision x;
double precision function erfc (x)
double precision x;
DESCRIPTION
erf returns the error function of x, defined as 2 / sqrt(Pi) ∗ integral[0, x] exp(-(t∗∗2)) dt
erfc, which returns 1.0 − erf(x), 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 (e.g., for x = 5, 12 places are lost).
SEE ALSO
NOTES
When compiling source with the -Qocs option, an explicit underscore needs to be added to the end of the routine names.
CX/UX Hf77 Fortran Reference Manual