While teaching in Pasadena, I wanted to use some local public data. While the City of Los Angeles had a variety of interesting, easy to use open data, it was a bit tougher to find interesting datasets on the City of Pasadena's open data platform (though it looks like the platform and navigation has been updated since then!). I finally came upon this dataset of traffic collisions in Pasadena.
I wanted to use this dataset with Mappa.js, but I had a problem... the coordinates weren't in a format I could use with Mappa.js. I needed latitude and longitude, and these coordinates were ESRI coordinates (specifically, ESRI 102645 (NAD 1983 StatePlane California V FIPS 0405 Feet)). I ultimately used the pyproj module to convert one to the other. From there, I filtered the data and wrote it to a JSON file which I then used to map the data using Mappa.js and p5.js.
