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NAME
erf, erfc - error function
SYNOPSIS
#include <math.h>
double erf(x)
double x;
double erfc(x)
double x;
DESCRIPTION
These functions calculate the error function erf(x) and the
complementary error function erfc(x) = 1 - erf(x). The
error criterion for both erf and erfc is relative.
DIAGNOSTICS
There are no error returns.