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valarray sin() Function in C++ with Examples

C++ valarray sin() Function: Here, we will learn about the sin() function, its usages, syntax and examples.
Submitted by Shivang Yadav, on May 08, 2022

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

Sin function (Mathematical Definition)

Mathematically, sine is a trigonometric function that relate to the angle of a right-angled triangle. Its value is the ratio of the length of side opposite to the angle and the hypotenuses.

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

The sin() function of valarray class is used to find the sin value of each element of the valarray. The method calculates the sine value and return a new valarray consisting of the sine resultant value.

Syntax

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

// or
sin(valarrayName)

Parameter(s)

The method accepts a single parameter. It is the valarray on which the sin() function is applied.

Return value

The method returns a valarray with an element whose value is equivalent to the sine of the value of the original valarray.

Example 1

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

int main()
{
    // Declaring valarray
    valarray<double> myvalarr = { 1, 0.2, 1.3, 2.4, 5 };

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

    // Creating a new valarray of sine values
    valarray<double> sinValarray;
    sinValarray = sin(myvalarr);

    cout << "\nThe elements of sin valarray is : ";
    for (double& ele : sinValarray)
        cout << ele << " ";

    return 0;
}

Output

The elements of valarray are : 1 0.2 1.3 2.4 5 
The elements of sin valarray is : 0.841471 0.198669 0.963558 0.675463 -0.958924 

The angles converted by the sine function are taken in radians and the normal angle we read are in degrees. Here, radian value is equivalent to the angles in degree.

180° = π radians = 3.14159
90° = π/2 radians = 1.5708
60° = π/3 radians = 1.0472
45° = π/4 radians = 0.785398
30° = π/4 radians = 0.523599

Now, let's see the sine values of these.

Example 2

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

int main()
{
    // Declaring valarray
    valarray<double> myvalarr = { 3.14, 1.5708, 1.0472, 0.785398, 0.523599 };

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

    // Creating a new valarray of sine values
    valarray<double> sinValarray;
    sinValarray = sin(myvalarr);

    // Printing the elements of valarray
    cout << "\nThe elements of sin valarray is : ";
    for (double& ele : sinValarray)
        cout << ele << " ";

    return 0;
}

Output

The elements of valarray are : 3.14 1.5708 1.0472 0.785398 0.523599 
The elements of sin valarray is : 0.00159265 1 0.866027 0.707107 0.5