Sparklines in D3

A couple weeks ago, Protovis, a visualization library I’d been using was deprecated in favor of D3 and I thought I’d share some of the work I’d done porting visualizations from the old to the new.

One example that Protovis has for which there is no corresponding tutorial is sparklines. This sparkline shows the San Diego Padres’ first 100 games of the 2011 season. Up ticks are wins and down ticks are losses. Red ticks show shutouts. This is similar to the visualization in Tufte’s “Beautiful Evidence” p. 54.

I created another simple visualization for the National League West. This shows all five teams of the NL West on a single graphic. It is pretty easy to adapt this code to a single sparkline. So far I have been fairly pleased with D3’s performance and the ease of use.

Visualizing Data: Startup Edition

Lately, I’ve been working on visualization some security data we have at work. While I can’t share exactly what I’m doing, I thought I’d share a little of what I’m doing.

I created a treemap of technology company market capitalization data as of today using Protovis. The different colors correspond to different sub-sectors. The startup data is hazy as there’s no publicly available market and I did the best I could. My goal was to compare the size of these technology companies and see if I could see anything interesting. One interesting note is that Facebook is about as big as the combined rest of the startups. Google and IBM rule the services world. Apple rules the hardware world, but I’m not sure I’d classify them as a hardware company.

Regardless, enjoy!