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valarray exp() Function in C++ with Examples

C++ valarray exp() Function: Here, we will learn about the exp() function, its usages, syntax and examples.
Submitted by Shivang Yadav, on May 12, 2022

The valarray class in C++ is a special container that is used for holding elements like an array and performing operations on them.

C++ STL std::exp(std::valarray) Function

The exp() function of the valarray class is used to calculate the value of e raised to the value of element. It returns a valarray with each element calculated using exp() function.

Syntax

template< class T >
valarray<T> exp( const valarray<T>& va );

// or
exp(valarrayName)

Parameter(s)

It accepts a single parameter which is the original valarray.

Return value

It returns a valarray of value e raised to the power of the elements of the original valarray.

Example 1

#include <iostream>
#include <valarray>
using namespace std;

int main()
{
    // Declaring valarray
    valarray<int> myvalarr = { 3, 6, 2, 5, 1 };

    // Printing the elements of valarray
    cout << "The elements of orignal valarray are : ";
    for (int& ele : myvalarr)
        cout << ele << " ";

    // Creating a new valarray
    valarray<int> expValarray;
    expValarray = exp(myvalarr);

    cout << "\nThe elements of exp valarray are : ";
    for (int& ele : expValarray)
        cout << ele << " ";

    return 0;
}

Output

The elements of orignal valarray are : 3 6 2 5 1 
The elements of exp valarray are : 20 403 7 148 2 

Example 2

#include <iostream>
#include <valarray>
using namespace std;

int main()
{
    // Declaring valarray
    valarray<double> myvalarr = { 3.1, -6, -0.2, 5, 1.7 };

    // Printing the elements of valarray
    cout << "The elements of orignal valarray are : ";
    for (double& ele : myvalarr)
        cout << ele << " ";

    // Creating a new valarray
    valarray<double> expValarray;
    expValarray = exp(myvalarr);

    cout << "\nThe elements of exp valarray are : ";
    for (double& ele : expValarray)
        cout << ele << " ";

    return 0;
}

Output

The elements of orignal valarray are : 3.1 -6 -0.2 5 1.7 
The elements of exp valarray are : 22.198 0.00247875 0.818731 148.413 5.47395