atanl() in C++

atanl(): This function is available in the file math.h. This function takes one argument. It computes the principal value of the arc tangent of arg. It returns the value in the range [-π,π].

Parameters: One parameter is required for this function.

arg: The value whose arc tangent value is to be determined. Floating-point value.

Syntax:

atanl(arg)

For Example:

atanl(0.5)  = > It returns the value 0.463648

Approach

C++

#include <bits/stdc++.h>
using namespace std;

int main()
{
    long double x = 0.5;
    cout << atanl(x) << "\n";

    return 0;
}