JavaScript array methods

JavaScript Array Methods Map, Reduce, Filter

Let us now try to see how JavaScript array methods Map, Reduce, and Filter work. The code snippets are shown below: To practice this tutorial, you need to have Visual Studio Code and NodeJS installed on your computer We will start by seeing the basic functionalities of the JavaScript array and then we will further use map, reduce, and filter methods to perform some actions on the array. The first step we need to take is to define an array with name ‘marks’ In this step, we defined an array with identifier marks with a size of six elements and then we populated the array with some values separated by commas. In the second step, we will perform some basic array functionalities like push, pop, and unshift and we will also see how we can traverse the array with for loop. There is an array method that helps you to validate if an element is present in it. So these were some basic array functionalities that we discussed. Now I will show you examples of performing actions on array elements with and without the JavaScript reduce method. First, we will see if we need to sum the array elements without reduce method see the following code snippet let totalMarks =0 for (let i=0; i<marks.length;i++){        totalMarks = totalMarks + marks[i]    } console.log(marks) // this will display the whole array in console console.log(“Sum of marks array =” + totalMarks) Second I will show you how we can simplify the above code snippet with the help of the JavaScript reduce method, see the following code snippet The following section explains how the JavaScript reduce method works The first argument is the callback function: We used only the first two arguments in our callback anonymous function i.e. <previousValue: sum>, <currentValue:…

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