dpythag.c

适合大型数值计算代码 现在网络上已经找不到了 购买需要20$

#include <math.h>
#define NRANSI
#include "nrutil.h"

double dpythag(double a, double b)
{
	double absa,absb;
	absa=fabs(a);
	absb=fabs(b);
	if (absa > absb) return absa*sqrt(1.0+DSQR(absb/absa));
	else return (absb == 0.0 ? 0.0 : absb*sqrt(1.0+DSQR(absa/absb)));
}
#undef NRANSI