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What I’ve done this year


I gave a talk at the big MathsJam conference at the start of this month. It happens annually, so I had a whole year to come up with something interestingly mathematical to entertain my fellow mathmos.

When it came time to decide on a topic, I realised I’ve done loads of stuff this year! It was really hard to choose. So, now MathsJam is over, I thought I’d collect together all the mathematical things I’ve done in the last 12 (-ish) months.

plotly.js is now open source

plotly is a fairly comprehensive tool for creating whizzy interactive charts from data. It provides a suite of tools to make a whole range of different types of charts.

Until now, it’s been a web service you send data away to in order to get a chart back. I’d always been wary of that, because I worry about what happens when Plotly the company gets sold off or goes bust, and the service gets shut down.

Well, now I can use a little bit of, because they’ve released the bit of the chart-drawing code that runs in your browser under the MIT open source licence, meaning anyone can use it independently of Plotly’s servers.

With just the open-source stuff, the process of creating a chart is quite torturous because you have to define what you want by following a fairly illegible JSON schema. That means there’s still a reason to use the proprietary stuff that gives you a nice interface from Python or R, though I suppose people will soon enough start making their own versions of those that just tie into the Javascript stuff.

More information

Plotly.js Open-Source Announcement

plotly.js on GitHub

Ask Clever Hans a question

I’ve put a very clever horse on the internet. He’s called Hans and I’ve made a little video about him.

You can ask Clever Hans your own questions! Go to and make sure your microphone is turned on. Another proviso: I think only Google Chrome supports the special technology I used to make Hans work. Sorry!

I’ll explain how Hans does his horsey magic below the fold.

László Babai reckons he can decide if two graphs are isomorphic in quasipolynomial time

László Babai in Chicago. Photo by Gabe Gaster, used with permission.

We’ve been slow to cover this, but if this week has taught us anything, it’s that taking your time over Important Maths News is always a good idea.

A couple of weeks ago, rumours started circulating around the cooler parts of the internet that László “Laci” Babai had come up with an algorithm to decide if two graphs are isomorphic in quasipolynomial time. A trio of mathematicians including Tim Gowers were on BBC Radio 4’s In Our Time discussing P vs NP while these rumours were circulating and made a big impression on Melvyn Bragg as they talked so excitedly about the prospect of something big being announced.

If Babai had done what the rumours were saying, this would be a huge advance – graph isomorphism is known to be an NP problem, so each step closer to a polynomial-time algorithm raises the P=NP excite-o-meter another notch.

Riemann Hypothesis not proved


Here’s a tweet from Alex Bellos this morning:

He’s right to be surprised – as reported in Vanguard, a Nigerian newspaper:

The 156-year old Riemann Hypothesis, one of the most important problems in Mathematics, has been successfully resolved by Nigeria Scholar, Dr. Opeyemi Enoch.

Suspicion levels are raised, as the paper also reports:

Three of the [Clay Millenium Prize] problems had been solved and the prizes given to the winners. This makes it the fourth to be solved of all the seven problems.

Unless we missed something, that’s not massively true – the only Millennium Prize problem solved so far is the Poincaré conjecture.

Make your own bauble with icosahedral symmetry with Shapeways


Internet 3D printing emporium Shapeways has released a nifty little tool to create your own unique Christmas bauble, which they’ll print out and send to you in time for the festive season.

It works by mapping a triangular design onto a blown-out icosahedron, and applying some “kaleidoscope effects”. As far as I can tell, that means they expand and rotate the patterns so they overlap.

There’s a selection of built-in patterns you can choose from, or you can upload your own pattern to make a really unique decoration. However, because the resulting object needs to exist in the real world, you need to take care to make sure it all comes out in one connected piece. Shapeways have written some very clear instructions about how to achieve that.

Play: Ornament Creator from Shapeways

via Vladimir Bulatov on Google+, who seems to work for Shapeways now. Exciting!