4 big differences between forEach and map in JavaScript

JavaScript has some methods that help us to iterate through Arrays. The two most used are foreach() and map() in Javascript. But I believe there is a lot of doubt between these two methods.

forEach and map in Javascript: Definitions

We will define each method, and where each one fits in, to try to understand better what we can do with each one:

The map() method gets a function as a parameter. This function is invoked for each Array element and, at the end, the method returns a completely new array filled with the results of the given function call.

const numbers = [5, 4, 3, 2, 1]

console.log(numbers.map(element => element * element)) //[ 25, 16, 9, 4, 1 ]

This means that it returns a new array that contains an image of each array element. It will always return the same number of items.

The forEach() method receives a function as an argument and executes it once for each Array element. However, instead of returning a new array as the map() method, it returns undefined.

const numbers = [5, 4, 3, 2, 1]

console.log(numbers.forEach(element => element * element)) //undefined

#javascript #programming #foreach

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4 big differences between forEach and map in JavaScript

4 big differences between forEach and map in JavaScript

JavaScript has some methods that help us to iterate through Arrays. The two most used are foreach() and map() in Javascript. But I believe there is a lot of doubt between these two methods.

forEach and map in Javascript: Definitions

We will define each method, and where each one fits in, to try to understand better what we can do with each one:

The map() method gets a function as a parameter. This function is invoked for each Array element and, at the end, the method returns a completely new array filled with the results of the given function call.

const numbers = [5, 4, 3, 2, 1]

console.log(numbers.map(element => element * element)) //[ 25, 16, 9, 4, 1 ]

This means that it returns a new array that contains an image of each array element. It will always return the same number of items.

The forEach() method receives a function as an argument and executes it once for each Array element. However, instead of returning a new array as the map() method, it returns undefined.

const numbers = [5, 4, 3, 2, 1]

console.log(numbers.forEach(element => element * element)) //undefined

#javascript #programming #foreach

Coy  Roberts

Coy Roberts

1600679940

Javascript Array forEach() Method Example

Javascript array foreach is an inbuilt function that can be used to execute a function on each item in the array. The forEach() method is called on the array Object and is passed the function that is called on each item in the array.  The  callback function can also take the second parameter of the index in case you need to reference the index of the current element in the array.

Understanding Javascript Array forEach

In a nutshell, Javascript forEach() method executes a provided function once for each array element. Javascript forEach only be used on the Arrays, Maps, and  Sets. This article briefly describes how to use the forEach() method to iterate the items of the array in JavaScript.

What’s the usual thing you do with an  array? Add or remove items from an array. Iterate through its items! This is where the forEach() array method shines.

Before we dive into seeing how forEach() works, we need to take a look at how looping works. Looping is a fundamental computer science concept. If you want to be a sound programmer, mastering loops are amidst the first steps you need to take.

Here’s an example of a for loop in Javascript.

let languages = ['Python', 'Javascript', 'PHP', 'Golang'];

for (i = 0; i < languages.length; i++) {
  console.log(languages[i])
}

#javascript #javascript array foreach #javascript foreach

Coy  Roberts

Coy Roberts

1600868220

Array Foreach, Map, Filter, Reduce, Concat Methods in Javascript

In this tutorial, we will see Javascript Array Foreach, Map, Filter, Reduce, Concat Methods. I dedicate this article only for these methods because, in Pure Functional Programming, this kind of method is required to perform some operations on an Array.

If you do not know What Pure Functions is, then check out my Pure Functions in Javascript article on this website.

Arrays

All the programming languages have this kind of Data Structure to hold and manipulate the data and Javascript is not different.

We all know Arrayscollection of variables, and we all have used to perform some operations like Creating an array, Removing an Item from an Array, Sorting the data of an Array and other manipulations.

In Functional Programming, we are using functions like foreach, map, filter, reduce, concatAll and other Higher Order Functions. So today I am describing these functions in deep and show you how you can use it in various scenarios.

#javascript #programming #foreach #map #filter #reduce

Rahul Jangid

1622207074

What is JavaScript - Stackfindover - Blog

Who invented JavaScript, how it works, as we have given information about Programming language in our previous article ( What is PHP ), but today we will talk about what is JavaScript, why JavaScript is used The Answers to all such questions and much other information about JavaScript, you are going to get here today. Hope this information will work for you.

Who invented JavaScript?

JavaScript language was invented by Brendan Eich in 1995. JavaScript is inspired by Java Programming Language. The first name of JavaScript was Mocha which was named by Marc Andreessen, Marc Andreessen is the founder of Netscape and in the same year Mocha was renamed LiveScript, and later in December 1995, it was renamed JavaScript which is still in trend.

What is JavaScript?

JavaScript is a client-side scripting language used with HTML (Hypertext Markup Language). JavaScript is an Interpreted / Oriented language called JS in programming language JavaScript code can be run on any normal web browser. To run the code of JavaScript, we have to enable JavaScript of Web Browser. But some web browsers already have JavaScript enabled.

Today almost all websites are using it as web technology, mind is that there is maximum scope in JavaScript in the coming time, so if you want to become a programmer, then you can be very beneficial to learn JavaScript.

JavaScript Hello World Program

In JavaScript, ‘document.write‘ is used to represent a string on a browser.

<script type="text/javascript">
	document.write("Hello World!");
</script>

How to comment JavaScript code?

  • For single line comment in JavaScript we have to use // (double slashes)
  • For multiple line comments we have to use / * – – * /
<script type="text/javascript">

//single line comment

/* document.write("Hello"); */

</script>

Advantages and Disadvantages of JavaScript

#javascript #javascript code #javascript hello world #what is javascript #who invented javascript

Silly mistakes that can cost ‘Big’ in Big Data Analytics

Big Data has played a major role in defining the expansion of businesses of all kinds as it helps the companies to understand their audience and devise their business techniques in accordance with the requirement.

The importance of ‘Data’ has been spoken very highly in the modern-day business. Thus, while using big data analysis, the companies must keep away from these minor mistakes otherwise it could have a major impact on their performances. Big Data analysis can be the silver bullet that can answer your questions and help your business to scale newer heights.

Read More: Silly mistakes that can cost ‘Big’ in Big Data Analytics

#top big data analytics companies #best big data service providers #big data for business #big data technology #big data mistakes #big data analytics