valarray exp() function in C++

The exp() function is defined in valarray header file. This function is used to calculate e raised to the power equal to the value of the element in valarray.

Syntax:

exp(varr);

Parameter: This function takes a mandatory parameter varr which represents valarray.

Returns: This function returns a valarray containing the exponential values of all the elements.

Below programs illustrate the above function:

Example 1:-

// C++ program to demonstrate
// example of exp() function.

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

int main()
{

    // Initializing valarray
    valarray<double>
        varr = { 1, 2, 3, 4, 5 };

    // Declaring new valarray
    valarray<double> varr1;

    // use of exp() function
    varr1 = exp(varr);

    // Displaying new elements value
    cout << "The new valarray with"
         << " manipulated values is : "
         << endl;

    for (double& x : varr1) {
        cout << x << " ";
    }

    cout << endl;

    return 0;
}

Output:

The new valarray with manipulated values is : 
2.71828 7.38906 20.0855 54.5982 148.413

Example 2:-

// C++ program to demonstrate
// example of exp() function.

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

int main()
{

    // Initializing valarray
    valarray<double>
        varr = { -1, 0, 3, 0, -5 };

    // Declaring new valarray
    valarray<double> varr1;

    // use of exp() function
    varr1 = exp(varr);

    // Displaying new elements value
    cout << "The new valarray with"
         << " manipulated values is : "
         << endl;

    for (double& x : varr1) {
        cout << x << " ";
    }

    cout << endl;

    return 0;
}

Output:

The new valarray with manipulated values is : 
0.367879 1 20.0855 1 0.00673795