Des-blog

A couple days ago, we got a bug report that left us shaking our heads in collective confusion. The trouble? This graph:

Notice that f(π) is returning “undefined.” Trace doesn’t fare any better. But tan(π) = 0, so √tan(π) should also equal 0. What gives?

Well, it turns out that the problem lies deep in the heart of the javascript. Look at what the chrome console is giving us:

Aha! We should be getting zero when we take tan(π), but we’re actually getting a very small negative number. And you can’t take the square root of a negative number. This actually makes perfect sense: javascript only uses an approximation for π, and an approximation for tangent. Combine them, and you can’t expect exact results! But it’s giving the wrong answer here, and we hate giving the wrong answer.

How would you solve this, javascript coders? (send us your solution at jobs@desmos.com….). As of tonight, we have a solution that we think is pretty clever. Here it is in action:

… and we can all enjoy our bug-free pi.

Occasionally, we see a graph that just blows us away with its beauty and ingenuity. Like this one:

[click on the image to play around with the graph yourself]

We reached out, and got the following response from its author, Amy:

My precalculus class had to make a graphed picture using the at least one of each of the trigonometric functions. It was time consuming and difficult to do on the TI84 so my friend recommended the Desmos website that she found through google. It was great! It made the project fun and cut my work time in half! I am currently a senior in high school.

It’s hard to describe, as an entrepreneur, the significance of a response like this. We wake up early, stay in late, work weekends, all with a vision of the impact that we can have. We want to believe that we’re making it cheaper and easier to graph equations, obviously. But that’s just a small part of our motivation. We’re driven by our vision of making math fun, of breaking down the barrier between the perceived mechanical coldness of equations and the humbling beauty of the world. We can talk about that all day, we can write code that we think has that effect. But it’s only when we see our ideals embodied in the incredible creativity of a real student – that’s what makes the long hours worth it.

Do you have a story of how you’ve used our calculator? Email us at calculator@desmos.com. There is nothing that keeps us going like hearing from real users.

Thank you, Amy. And incredible work.

In honor of Valentine’s Day, we’ve dressed A Better Calculator in pink and white and tied it with a bow:

Since we firmly believe that Math is Love, we’ve built in the ability for you to share Math-o-grams with the nerdy ones you love. What’s a Math-o-gram you ask? Just pick a graph (or create your own), write a bubbly, loving message, and email it out.

What chocolates an flowers do for the senses, these graphs will do for your brain. Happy February 14th!

Love,

Team Desmos