A lot of data? An array!

Muffin was wagging his tail pensively and squinting at your code. Then he took his tired eyes off the monitor, dialed the familiar number on the pager and said with a sigh: “Hi, team lead. Tell this rookie about refactoring.”

Surprisingly, the video blog was able to survive long enough, and today Muffin sent us data for the last month:

817, 1370, 752, 1247, 681, 1120, 915, 1281, 875, 1341, 757, 610, 812, 1170, 769, 1261, 845, 1289, 515, 1247, 845, 1311, 741, 1239, 812, 638, 877, 1242, 1159, 1372

To analyze this data, you will have to add 26 more variables to the current program. A lot of writing? We are about to get data for the year, too.

Your program works correctly, but adding new data to it is extremely time-consuming. Therefore, it’s time to refactor. Refactoring is changing the structure of a program while keeping its behavior the same. The purpose of our refactoring is to reduce the complexity of adding and modifying massive amounts of data.

Fortunately, there is a way to store large amounts of data. This structure is called an array. An array is a data type representing an ordered list of elements, each identified by an index.

Arrays are created using an array literal with square brackets. Inside the brackets, list the array values separated by commas. Like any other value, an array can be assigned to a variable:

var numbers = [1, 2, 3, 4, 5];

In the array you can store any data: strings, Boolean values, numbers and even other arrays.

We will do refactoring smoothly, without deleting the entire program, but rewriting its parts instead. At the first stage, we get rid of the individual variables for the data:

1. Let’s temporarily set the average value to zero.
2. Then create an array, in which we transfer the values ​​from the variables.
3. And pass this array to the command muffin.plot() instead of variables (fortunately, the command can work with arrays).
4. Now, when the variables for the data in the program are no longer used, we can go ahead and delete them.