请帮我解释一下~~~谢谢
应用递归算法求某数a的平方根.公式:x1=1/2(x0+a/x0)
帮我解释一下if( fabs(x1-x0)>=0.00001)什么意思
#include<stdio.h>
#include<math.h>
double fun(double a,double x0)
{ double x1,y;
x1=(x0+a/x0)/2.0;
if(fabs(x1-x0)>=0.00001)
y=fun(a,x1);
else y=x1;
return y;
}
main()
{ double x;
printf("Enter x:");scanf("%lf",&x);
printf("The square root of %lf is %lf\n",x,fun(x,1.0));
}