Mastering the minBy Function in JavaScript

Introduction

In this lab, we will be exploring the minBy function in JavaScript. The minBy function returns the minimum value of an array, based on a function that maps each element to a value. Through this lab, you will learn how to use minBy to find the minimum value of an array, using a provided function.

Skills Graph

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Function to Return Minimum Value of an Array

To start practicing coding, open the Terminal/SSH and type node.

This function returns the minimum value of an array, based on the provided function.

To do this, it uses Array.prototype.map() to map each element to the value returned by the function. It then uses Math.min() to get the minimum value.

const minBy = (arr, fn) => Math.min(...arr.map(typeof fn === "function" ? fn : (val) => val[fn]));

You can use this function by passing an array and a function. For example:

minBy([{ n: 4 }, { n: 2 }, { n: 8 }, { n: 6 }], (x) => x.n); // 2 minBy([{ n: 4 }, { n: 2 }, { n: 8 }, { n: 6 }], "n"); // 2

Min Array Value Based on Function

Introduction

Skills Graph

Function to Return Minimum Value of an Array

Summary

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