Found 10483 Articles for Web Development

Returning the highest number from object properties value – JavaScript

AmitDiwan
Updated on 18-Sep-2020 13:37:02

739 Views

Suppose, we have an object that contains rating of a property over some criteria like this −const rating = {    "overall": 92,    "atmosphere": 93,    "cleanliness": 94,    "facilities": 89,    "staff": 94,    "security": 92,    "location": 88,    "valueForMoney": 92 }We are required to write a JavaScript function that takes in one such object and returns the key value pair that has the highest value.For example, for this very object, the output should be −const output = {    "staff": 94 };ExampleFollowing is the code −const rating = {    "overall": 92,    "atmosphere": 93,   ... Read More

Find indexes of multiple minimum value in an array in JavaScript

AmitDiwan
Updated on 18-Sep-2020 13:35:48

600 Views

Suppose we have an array of numbers like this −const arr = [1, 2, 3, 4, 1, 7, 8, 9, 1];Suppose we want to find the index of the smallest element in the array i.e. 1 above.For this, we can simply use −const min = Math.min.apply(Math, arr); const ind = arr.indexOf(min);The above code will successfully set ind to 0, which indeed is correct.But what we want to achieve is that if there are more than one minimum elements in the array, like in the above array (three 1s), then we should return an array containing all the indices of minimum ... Read More

Writing a For Loop to Evaluate a Factorial - JavaScript

AmitDiwan
Updated on 18-Sep-2020 13:34:47

1K+ Views

We are required to write a simple JavaScript function that takes in a Number, say n and computes its factorial using a for loop and returns the factorial.For example −factorial(5) = 120, factorial(6) = 720Maintain a count and a result variable, keep multiplying the count into result, simultaneously decreasing the count by 1, until it reaches 1And then finally we return the result.ExampleFollowing is the code −const num = 14; const factorial = num => {    let res = 1;    for(let i = num; i > 1; i--){       res *= i;    };    return res; }; console.log(factorial(num));OutputThis will produce the following output in console −87178291200

Normalize numbers in an object - JavaScript

AmitDiwan
Updated on 18-Sep-2020 13:33:49

606 Views

Suppose, we have an object with strings mapped to numbers like this −const obj = {    num1: 45,    num2: 78,    num3: 234,    num4: 3,    num5: 79,    num6: 23 };We are required to write a JavaScript function that takes in one such object as the first argument and an array of strictly two numbers as the second argument.The second argument basically represents a range −[a, b] (b >= a)Our job is to normalize the object values according to the range.Therefore, the largest value of the object must become b and the smallest must become a. ... Read More

Implementing the Array.prototype.lastIndexOf() function in JavaScript

AmitDiwan
Updated on 18-Sep-2020 13:32:11

281 Views

The lastIndexOf() function in JS returns the index of the very last occurrence of the element, passed into it as an argument, in the array, if it exists. If it does not exist the function returns -1.For example −[3, 5, 3, 6, 6, 7, 4, 3, 2, 1].lastIndexOf(3) would return 7.We are required to write a JavaScript function that have the same utility as the existing lastIndexOf() function.And then we have to override the default lastIndexOf() function with the function we just created. We will simply iterate from the back until we find the element and return its index.If we ... Read More

Sum similar numeric values within array of objects - JavaScript

AmitDiwan
Updated on 18-Sep-2020 13:31:07

892 Views

Suppose, we have an array of objects like this −const arr = [    {"firstName":"John", "value": 89},    {"firstName":"Peter", "value": 151},    {"firstName":"Anna", "value": 200},    {"firstName":"Peter", "value": 22},    {"firstName":"Anna", "value": 60} ];We are required to write a JavaScript function that takes in one such array and combines the value property of all those objects that have similar value for the firstName property.Therefore, for the above array, the output should look like −const output = [    {"firstName":"John", "value": 89},    {"firstName":"Peter", "value": 173},    {"firstName":"Anna", "value": 260} ];For each object, we will recursively find their similar objects(Similar objects ... Read More

How to remove blank (undefined) elements from JavaScript array - JavaScript

AmitDiwan
Updated on 18-Sep-2020 13:29:52

698 Views

Suppose we have an array of literals like this −const arr = [4, 6, , 45, 3, 345, , 56, 6];We are required to write a JavaScript function that takes in one such array and remove all the undefined elements from the array in place. We are only required to remove the undefined and empty values and not all the falsy values.Use a for loop to iterate over the array and Array.prototype.splice() to remove undefined elements in place.ExampleFollowing is the code −const arr = [4, 6, , 45, 3, 345, , 56, 6] const eliminateUndefined = arr => {   ... Read More

Sort object array based on another array of keys - JavaScript

AmitDiwan
Updated on 18-Sep-2020 13:28:32

4K+ Views

Suppose, we have two arrays like these −const arr1 = ['d', 'a', 'b', 'c'] ; const arr2 = [{a:1}, {c:3}, {d:4}, {b:2}];We are required to write a JavaScript function that accepts these two arrays. The function should sort the second array according to the elements of the first array.We have to sort the keys of the second array according to the elements of the first array. This will produce the following output −const output = [{d:4}, {a:1}, {b:2}, {c:3}];ExampleFollowing is the code −const arr1 = ['d', 'a', 'b', 'c'] ; const arr2 = [{a:1}, {c:3}, {d:4}, {b:2}]; const sortArray = ... Read More

How to subtract elements of two arrays and store the result as a positive array in JavaScript?

AmitDiwan
Updated on 18-Sep-2020 13:27:01

3K+ Views

Suppose, we have two arrays like these −const arr1 = [1, 2, 3, 4, 5, 6]; const arr2 = [9, 8, 7, 5, 8, 3];We are required to write a JavaScript function that takes in two such arrays and returns an array of absolute difference between the corresponding elements of the array.Therefore, for these arrays, the output should look like −const output = [8, 6, 4, 1, 3, 3];We will use a for loop and keep pushing the absolute difference iteratively into a new array and finally return the array.ExampleFollowing is the code −const arr1 = [1, 2, 3, 4, ... Read More

Generating n random numbers between a range - JavaScript

AmitDiwan
Updated on 18-Sep-2020 13:25:46

257 Views

We are required to write a JavaScript function that takes in a number, say n, and an array of two numbers that represents a range. The function should return an array of n random elements all lying between the range provided by the second argument.ExampleFollowing is the code −const num = 10; const range = [5, 15]; const randomBetween = (a, b) => {    return ((Math.random() * (b - a)) + a).toFixed(2); }; const randomBetweenRange = (num, range) => {    const res = [];    for(let i = 0; i < num; ){       const random ... Read More

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