sortArrayDesc()

Step 1: Understanding The Problem

The function sortArrayDesc needs to sort an array in descending order. When an array of numbers is passed, the function should return a new array with the numbers sorted from the largest to the smallest.

For the purpose of this guide, we will use the JavaScript's built-in sort() function, and a custom comparison function to sort the array in descending order.

function sortArrayDesc(array) {

}

Step 2: Use the JavaScript's built-in sort() function

The sort() function, sorts the elements of an array in place and returns the array. The sort is not necessarily stable. The default sort order is according to the string Unicode code points.

However, we need to specify a custom sorting function for the sort() function to sort the numbers in descending order.

function sortArrayDesc(array) {
    return array.sort();
}

Step 3: Add a custom sorting function to the sort() function

We need to assign a custom sorting function to the sort() function as an argument. In our case, we need the function to sort numbers in descending order. We use b - a to sort in descending order because sort() function sorts in ascending order by default.

function sortArrayDesc(array) {
    return array.sort(function(a, b) {
        return b - a;
    });
}

Step 4: Testing the function

Now it's time to test our function. We will use an array of numbers and the function should return the same numbers of the array sorted in descending order.

console.log(sortArrayDesc([10, 5, 8, 1, 7]));  // [10, 8, 7, 5, 1]

Conclusion

Here's the final implementation of the sortArrayDesc function. This function takes an array of numbers as an argument and returns a new array of the same numbers sorted in descending order.

function sortArrayDesc(array) {
    return array.sort(function(a, b) {
        return b - a;
    });
}

As you can see, the JavaScript's built-in sort() function makes it easy to sort arrays in either ascending or descending order. You just need to pass a custom sorting function as an argument, depending on how you want to sort the array.