"Scraping for Data"
Betascape 2012, 9/23
What if the data you want isn't ready to be visualized? Well, you transform it. In this session, we'll take a look at how to free data that is locked up in various ways, such as RSS feeds and HTML pages, and then transform it into the best format for your visualization. We'll use Ruby and the command-line to scrape data from a few websites, and put it into a format suitable for a visualization. Bring your own examples of data on the web that needs to be "freed" and we'll work together to get that data out! Starting out as a short presentation, we'll quickly be writing code and then you're on your own to transform your own data.
Attendees: Install your laptop with Ruby and Rubygems to run the examples. Follow along in Perl or Python if you wish.
Level: Intermediate, comfort with programming required
Example 1 - read your water bill
Find out how much your neighbors pay on their water bills (scraping Baltimore City site)
Example 2 - map GPS encoded photos
View your GPS-encoded photos on a map (reading EXIF data from jpg images, such as from an iPhone camera)
ruby photos.rb > my_photos.html (open browser to view map)
Example 3 - Dave Troy's Tweets in Baltimore script
Capture tweets within a lat/long bounding box in real-time using the Twitter Streaming API. script
git clone https://gist.github.com/3742889 ruby stream.rb
Rickshaw to graph dataExample 4 - Using
Format your data, insert into web page, see visualization
open rickshaw/rickshaw.html in a browser