Nov 032014

Recently I bought a three-pack of these cool Nike Dri-FIT Crew Socks and I guess they mold them specifically for your left and right foot?

In getting ready for work this morning, I grabbed a pair of these bad boys, and I noticed that more often than not, the laundry place where I get my laundry done seems to pair them correctly (meaning that each “L” sock is paired with a corresponding “R” sock). I was wondering if they’re just hyper-considerate laundry folders over there, or if maybe it was just a coincidence.

Not recalling my statistics, I wrote a brute-force script to figure out what percentage of the time they would be bundled “correctly” when bundled at random:

And I found the answer to be an astonishing 40%!

$ python 3 -n 100000
3 pairs of socks
100000 iterations
{False: 60011, True: 39989}
Good 39.99% of the time 

I don’t know about you, but I find that percentage to be super high! We’re saying that when choosing socks in random order, that almost half of the time they’ll end up being bundled “correctly” with three bundles of properly matched “R” and “L” socks!

Update: I finished getting ready and hopped on my bike, and as I was commuting into work I started thinking about my results, specifically wondering if I could come up with a statistical explanation, and I think I figured it out.

Steps and corresponding probabilities:

  1. Choose one sock at random (cool 100% of the time, hard to mess this one up)
  2. Choose a sock that matches (cool 60% of the time – of the 5 remaining socks, 3 should be the correct match, and 2 the wrong one)
  3. Choose another remaining sock at random (cool 100% of the time)
  4. Choose a sock that matches this sock (cool 66.666…% of the time – of the remaining 3 socks, 2 are the correct match and 1 is wrong)
  5. The last two socks will always match each other (100%)

Now using statistics, you multiply the probabilities of these events happening (right?):

1.00 * 0.60 * 1.00 * 66.666 * 1.00

or in fractions

3/5 * 2/3





Yay, math!

Sep 182014

Preface: we have a few Graphite-powered Grafana dashboards at work that I wanted to rotate through on a regular basis on our team’s display monitor to give us a better idea of what’s going on.

I don’t know much about Applescript, but I found this article that offers some Applescript to rotates through Safari tabs.

That worked, but fullscreen Safari didn’t look great with tabs, so we used this article to create a Chrome version as well.

Here are the code snippets:

For those new to Applescript, open up Applescript Editor (you can find it using Spotlight) and try pasting the following code into the top pane and hitting the big green Run button:

display dialog "Hello world."


There are plenty of Applescript tutorials out there, so feel free to dive in.

update Damian walked in and cued us into Grafana’s Playlist feature. Doh! Oh well, it was still a good learning experience.

Sep 172014

I just came across (via jdp) this awesome command line dealie called pup:

Totally awesome! The HTML equivalent to jq, it allows you to parse HTML using CSS selectors from the command line.

For example, say I wanted to get the top 10 current headlines from Hacker News:

$ curl | pup td.title a text{} | head -n 10
Artificial sweeteners induce glucose intolerance by altering the gut microbiota
Show HN: CleverDeck – I built the spaced repetition app I always wanted
I was asked to crack a program in a job interview
Stuff Goes Bad: Erlang in Anger
Suture – Supervisor Trees for Go
The Design and Implementation of the FreeBSD Operating System, 2nd ed.
Easel Is Shutting Down
Dremel Releases a Mass-Market 3D Printer
The Traveling Salesman with Simulated Annealing, R, and Shiny
The New Yahoo Developer Network


How about another example: let’s grab all mentions of apple-related things on the first 5 pages of Hacker News to see how popular all of this insanity is these days:

$ for page in {1..5} ; do curl -s -S$page | pup td.title a text{} | awk '{print tolower($0)}' | egrep 'apple|ios|osx|swift|xcode|iphone' ; done ;
ios 8 reviewed
swype - ios 8 keyboard
stripe lands apple in quest for $720b in payments
ios8 adoption, hour by hour
ios 8 review
why apple didn't use sapphire for iphone screens
a history of misses for radioshack
predictive photo sharing with ios8
everything that went wrong while building the tumblr ios share extension
apple pay and nfc are obsolete: this is how payments could work in the future
the iphones 6
apple watch: initial thoughts and observations
build your own apple ibeacon with a raspberry pi
interactive iphone 6 experiment in webgl

So awesome!!! Thank you Eric Chiang!