JavaScript: Get every n^th element in a given array

JavaScript fundamental (ES6 Syntax): Exercise-21 with Solution

Every nth Element in Array

Write a JavaScript program to get every n^th element in a given array.

• Use Array.prototype.filter() to create a new array that contains every nth element of a given array.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
// Define a function called `every_nth` that filters an array and returns every nth element.
const every_nth = (arr, nth) => arr.filter((e, i) => i % nth === nth - 1);

// Example usage
console.log(every_nth([1, 2, 3, 4, 5, 6], 1)); // [1, 2, 3, 4, 5, 6]
console.log(every_nth([1, 2, 3, 4, 5, 6], 2)); // [2, 4, 6]
console.log(every_nth([1, 2, 3, 4, 5, 6], 3)); // [3, 6]
console.log(every_nth([1, 2, 3, 4, 5, 6], 4)); // [4]

Output:

[1,2,3,4,5,6]
[2,4,6]
[3,6]
[4]

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-1-21 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that returns every nth element from an array using a loop or functional approach.
• Write a JavaScript function that filters an array to include only elements at positions that are multiples of n.
• Write a JavaScript program that slices an array based on a given interval and returns the resulting elements.

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