📅  最后修改于: 2020-09-25 07:54:59             🧑  作者: Mango
C++中的lround() 函数对最接近参数的整数值进行四舍五入,一半的情况舍入为零。返回的值是long int类型。它类似于round() 函数,但返回一个long int,而round返回与输入相同的数据类型。
long int lround(double x);
long int lround(float x);
long int lround(long double x);
long int lround(T x); // For integral type
lround() 函数采用单个参数,并返回long int类型的值。此函数在
lround() 函数将单个参数值取整。
lround() 函数返回最接近x的整数值,中途情况从零舍入。返回的值是long int类型。
#include
#include
using namespace std;
int main()
{
long int result;
double x = 11.16;
result = lround(x);
cout << "lround(" << x << ") = " << result << endl;
x = 13.87;
result = lround(x);
cout << "lround(" << x << ") = " << result << endl;
x = 50.5;
result = lround(x);
cout << "lround(" << x << ") = " << result << endl;
x = -11.16;
result = lround(x);
cout << "lround(" << x << ") = " << result << endl;
x = -13.87;
result = lround(x);
cout << "lround(" << x << ") = " << result << endl;
x = -50.5;
result = lround(x);
cout << "lround(" << x << ") = " << result << endl;
return 0;
}
运行该程序时,输出为:
lround(11.16) = 11
lround(13.87) = 14
lround(50.5) = 51
lround(-11.16) = -11
lround(-13.87) = -14
lround(-50.5) = -51
#include
#include
using namespace std;
int main()
{
int x = 15;
long int result;
result = lround(x);
cout << "lround(" << x << ") = " << result << endl;
return 0;
}
运行该程序时,输出为:
lround(15) = 15
对于整数值,应用lround 函数将返回与输入相同的值。因此,在实践中,它通常不用于积分值。