Creating a Zero-Filled Array in JavaScript
A zero-filled array is an array whose value at each index is zero.
Below are the methods used for creating a Zero-Filled Array in JavaScript:
Table of Content
- Array.prototype.fill
- Using Apply() and Map()
- Using Array.from()
- Using for loop
- Using Lodash _.fill() Method
Method 1: Array.prototype.fill
The fill() method is used to change the elements of the array to a static value from the initial index (by default 0) to the end index (by default array.length). The modified array is returned.
Syntax:
fill(value, start, end)
Example: The following code snippet demonstrates the fill() method with 0 value.
Javascript
const arr = new Array(5).fill(0); console.log(arr); |
[ 0, 0, 0, 0, 0 ]
Array constructor takes the size of an array as a parameter if we pass one argument into it. fill() method takes the value we want to fill in the array.
Method 2: Using Apply() and Map()
In the below example, we use the apply() method to create an array of 5 elements that can be filled with the map() method. In the map() method, we pass in a callback that returns 0 to fill all the indexes with zeros.
Example: Array.apply() method is used to create an empty array in which we can use the map() method to store each element as key-value pair.
Javascript
const arr = Array.apply( null , Array(5)).map(() => 0); console.log(arr); |
[ 0, 0, 0, 0, 0 ]
Method 3: Using Array.from()
This method is used to create a new,shallow-copied array from an array-like or iterable object.
Syntax:
Array.from(arrayLike, (element) => { /* ... */ } )
Example: Array.from() is called which lets us map an empty array of size 5 to an array with some elements inside. The second argument is a callback that returns 0 which is used to fill the array.
Javascript
const arr = Array.from(Array(5), () => 0) console.log(arr); |
[ 0, 0, 0, 0, 0 ]
The same result can be obtained by passing an object with the length property using the Array.from() method.
Javascript
const arr = Array.from({ length: 5 }, () => 0) console.log(arr); |
the
[ 0, 0, 0, 0, 0 ]
Method 4: Using for loop
JavaScript for loop is used to iterate the elements for a fixed number of times. JavaScript for loop is used if the number of the iteration is known.
Syntax:
for (statement 1 ; statement 2 ; statement 3){
code here...
}
Example: We will use the for loop for creating a zero-filled array.
Javascript
let zeroArr = [] for (i = 0; i < 5; i++) { zeroArr[i] = 0; } console.log(zeroArr); |
[ 0, 0, 0, 0, 0 ]
Method 5: Using Lodash _.fill() Method
Lodash _.fill() method is used to fill a set of values into the array in a given range.
Syntax:
_.fill(array, value, startIndex, endIndex);
Example: This example shows the use of the Lodash _.fill() method.
Javascript
// Method 5: Using Lodash _.fill() Method const arrayLength = 10; // Set the desired length of the array const zeroFilledArray = _.fill(Array(arrayLength), 0); // Display the result console.log(zeroFilledArray); |
Output:
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]