GIS mapping with Python

Driving times from San Mateo County Forensic Lab to the rest of the bay area. Numbers are in minutes. Bright splotches are multiples of 10 minutes. Speed limits for each road class are from the TMRS project and might be experimental. There's a suspicious road classification on Willow Road at the east end of the Dumbarton Bridge that might be throwing off all the Fremont times. Code is in CVS at the tag 'sanmateo1'.

I presented the San Mateo image at dorkbot. Here is a photo of my presentation.

I made plots of driving times from my house, with every multiple of 5 minutes highlighted in yellow, and every minute alternating between light and dark. Red increases gradually.

Before I connected some gaps in the bridges, I was getting this wrong image. Here's the corrected one.

Here's a first version of running shortest-paths on the map. Streets are not yet weighted differently (and the coord system is still in degrees).

I also plotted the streets in the San Francisco Bay Area using these colors for the first letter of the street (except freeways):

Here is a similar google maps view. Mine looks stretched in width because Google's map uses some "reasonable" projection, whereas mine uses a "very simple" one.

This is based on my previous work with TMRS. Most of the new work was converting the drawing from pygame to a new python binding to the excellent agg library. The street data is from TIGER.

Code is in CVS at the tag 'color_first_letter'. viewcvs is here.

Related work

TimeContours

Travel-time Maps and their Uses