精度问题-浮点数的比较（C++）

#include 
using namespace std;
#include
const double eps=1e-8;//10^(-8)
//加上括号，防止宏定义可能带来的错误
#define Equ(a,b) ((fabs((a)-(b)))<(eps))//等于运算符==
#define More(a,b) (((a)-(b))>(eps))//大于运算符>
#define Less(a,b) (((a)-(b))<(-eps))//小于运算符<
#define MoreEqu(a,b) (((a)-(b))>(-eps))//大于等于>=
#define LessEqu(a,b) (((a)-(b))<(eps))//小于等于<=  
int main()
{
    double d1=3.14;
    if(Equ(d1,3.14))
    {
        cout<<"true"<<endl;
    }else
    {
        cout<<"false"<<endl;
    }
    if(More(3.14,3.12))
    {
        cout<<"true"<<endl;
    }
    if(Less(3.14,3.15))
    {
        cout<<"true"<<endl;
    }
    if(MoreEqu(3.14,3.14))
    {
        cout<<"true"<<endl;
    }
    if(LessEqu(3.14,3.14))
    {
        cout<<"true"<<endl;
    }
    return 0;

}