Find Matching Keys

Group Elements By Count

In this lab, we will learn about the countBy function, which is used to group the elements of an array based on the given function and returns the count of elements in each group. We will explore how this function can be used to map values of an array to a function or property name and how to create an object to count the elements in each group using Array.prototype.reduce(). We will also look at several examples to understand how to use this function in real-world scenarios.

Sorting Object Arrays by Custom Order

In this lab, we will be exploring how to order an array of objects based on a given property and a custom order array. We will be using a combination of Array.prototype.reduce() and Array.prototype.sort() to create a new array that is sorted based on the order provided in the order array. This lab is a great opportunity to learn how to manipulate arrays of objects in JavaScript.

Implementing the Summary

In this lab, set in the bustling startup scene of 'FinTech Valley', you'll step into the shoes of Alex, a budding software engineer tasked with enhancing the financial tracking system for a rapidly growing tech company. The company's financial team needs a dynamic way to view the overall financial health of the organization. Your goal is to implement a feature in their existing web-based accounting application that calculates and displays the total income, total expenses, and net balance, providing real-time financial insights.