C++ Reference Manual

C++ Library Function <cmath>

C ++nexttoward() Function Usage and Example

The nexttoward(x, y) function in takes two parameters and returns the next representable value after x in the y direction.<cmath>The function in

It is defined in the header file.nextafter()The same, except that the second parameter of nexttoward() is always of type long double.

nexttoward() prototype[From C ++ 11Standard begins]

double nexttoward(double x, long double y);
float nexttoward(float x, long float y);
long double nexttoward(long double x, long double y);
double nexttoward(T x, long double y);　//　For integral type

The nexttoward() function takes two parameters and returns a value of type double, float, or long double.

nexttoward() parameters

• x：Basic value.

• y：Approximate the value of the return value.

nexttoward() return value

The nexttoward() function returns the next representable value after x in the y direction.

Example1：The nexttoward() function in C ++How does it work?

#include <iostream>
#include <cmath>
using namespace std;
int　main()
{
　　　　long double y =　-1.0;
　　　　double x = 0.0;
　　　　
　　　　double result = nexttoward(x, y);
　　　　cout　<<　"nexttoward(x,　y)　=　"　<<　result　<<　endl;
　　　　return　0;
}

When running the program, the output is:

nexttoward(x,　y)　=　-4.94066e-324

Example2：The nexttoward() function of integer type

#include <iostream>
#include <cmath>
#include <climits>
using namespace std;
int　main()
{
　　　　long　double　y　=　INFINITY;
　　　　int　x　=　INT_MAX;
　　　　double　result　=　nexttoward(x,y);
　　　　cout　<<　"nexttoward(x,　y)　=　"　<<　result　<<　endl;
　　　　return　0;
}

When running the program, the output is:

nexttoward(x,　y)　=　2.14748e+09

C++ Library Function <cmath>