C/math.h/erf
erf: returns the error function of arg
//Header file: #include <math.h>
//Declaration: float erff(float arg);
double erf(double arg);
long double erfl(long double arg);
#include <math.h>
#include <stdio.h>
int main(void)
{
printf("Value of e to the first: %f.", erf(1.0));
}
/*
Value of e to the first: 0.842701.*/