show and tell for hackers in DC.

Round 20: Severe Municipal Jazz

11 May 2015

Here are the Hackpad presentation notes from Round 20: Severe Municipal Jazz.

Speaker 1: Travis Hoppe


Code lives at:

Presentation lives at:

todayAIlearned is an attempt to mine Wikipedia for interesting things!

Supervised machine learning requires a massive tagged collection of high-quality data to be effective. Fortunately the past submissions of to r/TIL have done just that.

Reddit’s Today I Learned: a collection of facts that other people have found interesting. Data Collection, Downloaded all popular posts with high score that are from Wikipedia. Tokenize words & do data cleansing & used Google Word2Vec: training classifier for the words.

Ended up with a true positive rate of 10%, but a true negative rate of 99.8%, meaning we can find interesting things without too much work!

Speaker 2: Ben Klamens

POSIX Shell Scripting to draw card images

Ben designed a complicated series of shell scripts to creates pictures for an upcoming card game Bamboo Harvest.

Designed the card game to be a geometric, resource-building game; taking the game to Gen Con to demo it.

Use pipes to concatenate image blocks together.

Lot’s of companies exist to print the cards if you’re interested (ex. printandplay).

Speaker 3: Jess Garson

Movie sentiment scores

Code lives at

Jess shows off her attempts to predict a sentiment score of how positive or negative a movie review is using a Rotton Tomato review. This is quite challenging, since Rotten Tomatoes ratings are often very sarcastic … something machines don’t handle very well.

The project was inspired by a Kaggle contest, great way to start Machine Learning!

Used Logistic Regression and experimented with other classifiers. Used Google’s Word2Vec a deep learning tool to figure out the meaning of a word, though it didn’t work as well as expected.

Jess wants everyone to come to Machine learning Fridays for more awesome projects like this!

Speaker 4: Reed Spool

A Simple Stack Based Programming Language

“Why the hell aren’t we writing programming languages all the time, aren’t they so much fun!?

Reed wanted to teach us a programming language in the scant five minutes we allotted.

A simple post-fix notation language that went something like this:

  1. Parse token
  2. Add value to the stack
  3. If operands, take values of the stack and compute

Project started by trying prove a point that I could write a programming language in 15 minutes.

Supporting more than one level of parentheses is really challenging since they could be composed within one another; postfix notation doesn’t support this. So this project doesn’t support any parentheses.

An example of a Simple Stack Based Langauge that he wrote before.

A URL programming language:

Why Concatenative Programming Matters:

Speaker 5: Alec Dhuse

Printable guides for Rock Climbing

Demo at

Alec is a rock climber, and wants to provide a printable tool for other like-minded individuals.

Why not use a phone app? “Good idea to have paper and not a phone when climbing in RL”. Seems obvious enough.

His program creates up-to-date guidebook for destinations automagically and loads data from his custom database. Creates maps using Leaflet.js, adds information until it runs out of room on the page.

Arranges pages in a way so that you can print and fold the paper into a booklet. Learned to use @media CSS setting to handle special print options. Chrome respects the printing CSS rules the best.

Inspired by

Thanks to everyone who presented, everyone who attended, @LauraNLorenz for the pictures, and of course thanks to our favorite WeWork for hosting!

Round 21: Myo My is already scheduled, so RSVP and sign up to present!