fgauss.cpp

c经典算法(包括源码)

void fgauss(double x, double a[], double& y, double dyda[], int na)
{
	y = 0.0;
	for (int i = 1; i<=na - 1; i=i+3)
	{
		double arg = (x - a[i + 1]) / a[i + 2];
		double ex = exp(-(arg * arg));
		double fac = a[i] * ex * 2.0 * arg;
		y = y + a[i] * ex;
		dyda[i] = ex;
		dyda[i + 1] = fac / a[i + 2];
		dyda[i + 2] = fac * arg / a[i + 2];
	}
}