store arbitrarly large vector of doubles c++

To store an arbitrarily large vector of doubles in C++, you can follow these steps:

Include the necessary header files: Begin by including the required header files for working with vectors and doubles in C++. You will need to include the <vector> header for vectors and the <cstdlib> header for the std::size_t type.
Declare the vector: Declare a vector to store the doubles. You can use the std::vector<double> type to create a vector that can hold doubles.
Initialize the vector: Initialize the vector by calling its constructor. You can use the std::vector<double> myVector; syntax to create an empty vector.
Add elements to the vector: Use the push_back() function to add elements to the vector. The push_back() function appends an element to the end of the vector. For example, you can use myVector.push_back(3.14); to add the value 3.14 to the vector.
Repeat step 4 as needed: Repeat step 4 to add more elements to the vector. You can add as many elements as you need, and the vector will automatically resize itself to accommodate the additional elements.
Access elements in the vector: To access elements in the vector, you can use the subscript operator []. For example, myVector[0] will give you the first element in the vector.
Iterate over the vector: You can use a range-based for loop to iterate over the elements in the vector. This allows you to perform operations on each element in the vector. For example:

for (const auto& element : myVector) {
    // Do something with 'element'
}

Retrieve the size of the vector: To retrieve the size of the vector (i.e., the number of elements it contains), you can use the size() function. For example, myVector.size() will give you the number of elements in the vector.

Here is an example that demonstrates these steps:

#include <vector>
#include <cstdlib>

int main() {
    std::vector<double> myVector;
    myVector.push_back(3.14);
    myVector.push_back(2.718);
    myVector.push_back(1.618);

    for (const auto& element : myVector) {
        // Do something with 'element'
    }

    std::size_t vectorSize = myVector.size();

    return 0;
}

This code declares a vector called myVector, adds three elements to it, iterates over the elements, and retrieves the size of the vector.