Archive for the ‘Uncategorized’ Category

HaskSymb: An Experiment in Haskell Symbolic Algebra

June 1, 2012

One interesting detour I took this last month was writing a toy Haskell Symbolic Algebra library, HaskSymb. It takes advantage of Quasi-Quoters and View Patterns to do awesome math pattern matching and enable one to write beautiful code.

An example of its use:

> -- Let's make some variables!
> let (a,b)  = (V "a", V "b")
> -- Basic Expression manipulation
> (a+1)^3
(a + 1)³
> expand $ (a+1)^3
a³ + a² + a² + a² + a + a + a + 1
> collectTerms $ expand $ (a+1)^3
a³ + 3a² + 3a + 1

The interesting part, however, is the code for expand, collectTerms and friends. It’s extremely pretty. For example:

expand [m| a+b |] = expand a + expand b
expand [m|a*(b+c)|] = expand (a*b) + expand (a*c)
expand a = a

Read more on github. You can also find some discussion on the Haskell reddit.

Toronto RepRap User Group #3 = Great Success

March 1, 2012

I was the organizer of the most recent meeting of the Toronto RepRap User Group. It went excellently, with a turn out of about twenty people and five printers. We had a number of talks that were filmed by Socrates from the Singularity Weblog. In all, an awesome outcome!

Atendees look at a printer at the third Toronto RepRap User Group

Attendees also saw the first public demonstration of a collaboration between myself and my friend Rob, a web interface for ImplicitCAD. It’s still very much in development and I won’t be talking about it any further till the release of ImplicitCAD 0.0.2 (in a week or two).

A web interface for ImplicitCAD is demonstrated

You can read more and find links to the videos of the talks at the hacklab blog.

Quantified Hacklab

February 11, 2012

I’m very excited about a new project I’m collaborating on with my friend Sen: Quantified Hacklab. Inspired by Quantified Self, we’re analyzing the information that we naturally generate by living so close to technology in the hopes of better understanding our community. Also because we like data and pretty graphs.

You can read about some of our very initial results on the Hacklab Blog. To whet your appetite:

Hacklab's Activity according to doorbot for 2009,2010, and 2011; 7 day sum

ImplicitCAD 0.0.1 Release

February 6, 2012

I’m pleased to announce the second release of ImplicitCAD: 0.0.1. (The first release was 0.0.0 because 0 is the true first ordinal.)

Variable Twist Extrusion of a Rounded Union in ImplicitCAD

The point of this release is somewhat arbitrarily chosen. We were over due for one and no clean break was in sight. Then I woke up with a nasty headache and couldn’t seem to code, so I thought I’d do a release instead.

I’m going to try and martial together my thoughts and discuss changes in this release and what’s coming up. The TL;DR is that ImplicitCAD is going exciting places and if you are willing to tolerate bugs and file bug reports, you should become a beta user for it.


DIY Bio Toronto Meetup 1

January 20, 2012

On January 11th, we had the first DIY Bio Toronto Meetup at hacklab. To quote the description of DIY Bio Toronto:

Do-it-yourself biological innovation! We’re inspired by the California group “biocurious”, like them, we believe in the power of open source, open access, and learning in community. We believe this philosophy should be applied to biology! Wouldn’t it be great to have a biology-based maker space here in Toronto? Join us and help make that a reality! (more…)

Fractal Holiday/Solstice/Christmas Cards!

December 24, 2011

It’s that time of the year again: I’m making my fractal Holiday cards! I slacked last year and only made a few, but I’m back at it.

Christopher Olah's fractal Christmas cards from 2011

Previous years, I’d made up fractals for my cards. This year I just explored the Mandelbrot set and found cool looking regions. Since I obsessed over my choice of pictures, it took me a while to make them  — I’ve made about twenty so far, and still need to make more! (more…)

Project Shellter

December 22, 2011

A couple years ago, I wrote a patch for sage, an open source alternative to programs like Mathematica and Matlab, to allow it to export surfaces as STLs for 3D printing. Since then, I’ve seen a few uses of it pop up. Recently, it has been used for something extremely awesome: Project Shellter!

A 3D Printed Hermit Crab Shell

A 3D Printed Hermit Crab Shell (source)

They’re 3D printing hermit crab shells! And the shells are being adopted!

A Hermit Crab in a 3D Printed Shell

A Hermit Crab in a 3D Printed Shell (source via makerbot)

As someone who kept hermit crabs when I was younger, I think this is awesome!

Makerbot has a more thorough blog post, with a video of the shell being adopted.

Open Source 3D Printing: The Printers, Toolchain, & Things (GTALUG talk)

November 10, 2011

Last night I gave a talk, “Open Source 3D Printing: The Printers, Toolchain, & Things”, at the Greater Toronto Area Linux User Group (GTALUG). In addition to being the longest talk I’ve given thus far, at 90 minutes, I think it was the best. I feel more relaxed and in control with every talk I give.

For reference, I’m making the slideshow available.

Producing Lenses with 3D Printers (OHJ Paper)

November 9, 2011

I finally wrote up my results on producing lenses with 3D printers, which I’ve been working on since September, as a paper which I submitted to the Open Hardware Journal. It was published in their first issue (stand alone PDF of my paper) at the beginning of the month.

Chris Olah's 3D printer produced lens mangifies text on a poster

A number of people were excited by my paper, and I’ve had several email correspondences about it since publication. NBitWonder had a post about it.

It’s exciting to see such interest in my work.

Manipulation of Implicit Functions (With an Eye on CAD)

November 6, 2011

Most people are familiar with the equation for a circle, x^2+y^2 = r^2:

I prefer to think of it as the curve where f(x,y) = \sqrt{x^2+y^2}-1 is zero — the locations where the Euclidean distance from (0,0) is one.


Redacting October Review

November 2, 2011

Over the last few months, I’ve really enjoyed posting about what I’ve been doing in my life. I was looking forward to, several years from now, printing out all my month (or earlier, week) reviews and looking over them — and what people had said in the comments.

Unfortunately, a rather unpleasant person decided to take advantage of my openness and… Well, after what happened, I no longer feel comfortable continuing as I had. I really wish this wasn’t the case.

I’ve spent the last few weeks thinking about what I still do feel comfortable posting about, and I’ve concluded that I feel OK positing about most non-personal things. (No, this internal debate wasn’t the only reason you haven’t seen any posts from me — I’ve been super busy! — though it was part of my excuse to myself.)

I still intend to write an October Review, but it won’t be public. Hopefully, at some point, I’ll be able to retroactively publish my monthly reviews.

3D Printing Awesome Things (SoOnCon 2011 Talk)

October 3, 2011

I was rather nervous about giving my 1 hour SoOnCon talk, 3D Printing Awesome Things, especially after how my NYC Maker Faire talk went. Apparently I’d learned a lot from my NYC Maker Faire talk, and it went awesome! You can see my slide show.

The talk was mostly about interesting tricks I’d seen or come up with for printing awesome things, with examples of applications. I passed around dozens of examples. I actually only spoke for about forty minutes, leaving the last 20 for other people to share things that they’d seen or done themselves.

Many interesting things came out of the ensuing conversation. The ones that come to mind are:

  • cyclone’s Filament Colorizer
  • machinable wax as a medium for casting
  • Brainstorming for ways to print conductive parts. It’s not my area of expertise so I don’t know if any of these ideas are novel, but they’re interesting regardless. My notes from this are:
    • Solder paste (modified): Inject, reflow (heated platform?)
    • Acetone + silver
    • Conductive Ink

After a talk, a number of people told me that it was good, which was really comforting. I felt like it went well, but hearing people who sat through it agree was great! I was particularly touched by the person who told me that they hadn’t been using their spaces printer because they didn’t like the texture of printed objects, but would now that they’d seen the different post-processing techniques I use.

I feel like the success of this talk was partly due to it being a much easier and less technical topic than the Maker Faire one, me being a little bit less sleep deprived, but also simply that I’ve got better at giving talks having. Having physical examples to pass around was an awesome strategy, as well.

NYC Maker Faire Talk: Programmatic CAD

September 22, 2011

In addition to running a booth at Maker Faire this weekend, I gave a talk on programmatic CAD and its future.

My only public speaking experience prior to this was doing was doing workshops at hacklab and presentations to my classmates in high school and while this was a non-trivial amount of practice (in grade 10, I ended up teaching two semesters of the physics course I was taking in the form of seminars every class because the teacher didn’t know anything) it was all small scale (at max 15 people), highly interactive and mostly improvised on the spot. In other words, nothing at all like speaking at NYC Maker Faire.


Understanding Pascal’s Triangle

August 29, 2011

How many ways are there to arrange “ABC“? ABC, ACB, BAC, BCA, CBA, CAB. So 6 different ways. But could we have determined it in a way that didn’t involve us listing all the cases? The answer is yes, and welcome to the wonderful world of combinatorics. (more…)

The Real 3D Mandelbrot Set

August 8, 2011

Perhaps more than any other area of serious mathematics, fractals and more specifically the Mandelbrot set, have attracted a great deal of public interest. Continuing this pattern, the Mandelbulb set caused a great deal of excitement. As the Mandelbulb website it says, however, “there’s good reason to believe that it isn’t the real McCoy.” And so the question is left hanging, what is the real 3D Mandelbrot Set? In this essay, I will present the fractal that I believe deserves this position and why this is the case. (more…)