JavaScript Math Oddities

Sometimes, JavaScript does weird math! Try adding 0.1 + 0.2 in your NodeJS terminal. What did you get?

Hint: It's not 0.3!

The function SMath.approx() is an attempt to mitigate some of the issues that arise when doing arithmetic with non-whole numbers.

Installation

Follow these steps to create a new project workspace and install the smath dependency to run this example.

# Create and open project folder
mkdir JavaScript_Math_Oddities_demo
cd JavaScript_Math_Oddities_demo
# Initialize project and install dependencies
npm init -y
npm i smath@1.12.0
# Create and open source file
touch "JavaScript Math Oddities.mjs"
open "JavaScript Math Oddities.mjs"
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Source

Copy and paste this source code into JavaScript Math Oddities.mjs.

import { SMath } from 'smath';

// Determine the value of 0.1 + 0.2 using vanilla JavaScript and SMath
console.log('0.1 + 0.2 == 0.3 is ' + (0.1 + 0.2 == 0.3));
console.log('SMath.approx(0.1 + 0.2, 0.3) is ' + SMath.approx(0.1 + 0.2, 0.3));
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Output

In JavaScript_Math_Oddities_demo/, execute JavaScript Math Oddities.mjs with NodeJS to generate an output.

node "JavaScript Math Oddities.mjs"
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You should expect to see an output similar to the one below.

0.1 + 0.2 == 0.3 is false
SMath.approx(0.1 + 0.2, 0.3) is true
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