Sum an Array of Numbers with JavaScript
It's rare that I'm disappointed by the JavaScript language not having a function that I need. One such case was summing an array of numbers -- I was expecting Math.sum or a likewise, baked in API. Fear not -- summing an array of numbers is easy using Array.prototype.reduce!
const numbers = [1, 2, 3, 4];
const sum = numbers.reduce((a, b) => a + b, 0);
The 0 represents the starting value while with a and b, one represents the running total with the other representing the value to be added. You'll also note that using reduce prevents side effects! I'd still prefer something like Math.sum(...numbers) but a simple reduce will do!
![Creating Scrolling Parallax Effects with CSS]()
Introduction
For quite a long time now websites with the so called "parallax" effect have been really popular.
In case you have not heard of this effect, it basically includes different layers of images that are moving in different directions or with different speed. This leads to a...
![How to Create a Twitter Card]()
One of my favorite social APIs was the Open Graph API adopted by Facebook. Adding just a few META tags to each page allowed links to my article to be styled and presented the way I wanted them to, giving me a bit of control...
![MooTools Overlay Plugin]()
Overlays have become a big part of modern websites; we can probably attribute that to the numerous lightboxes that use them. I've found a ton of overlay code snippets out there but none of them satisfy my taste in code. Many of them are...
![RealTime Stock Quotes with MooTools Request.Stocks and YQL]()
It goes without saying but MooTools' inheritance pattern allows for creation of small, simple classes that possess immense power. One example of that power is a class that inherits from Request, Request.JSON, and Request.JSONP: Request.Stocks. Created by Enrique Erne, this great MooTools class acts as...
Initializing with 0 might not be necessary since it takes the value from the first item in the array if not provided (and then skips the first item for the rest). It’s very slightly slower to set it to 0.
Here’s what I wonder though… Suppose this were in some
math.jsmodule. Would it besum(nums)orsum(...nums)?sum([1,2,3])orsum(1,2,3)? I kinda prefer the latter.