I set out to create a map that showed urban sprawl in the central valley of California. Geoserver, OpenLayers and PostGIS are the technologies in this demo. (the linux server itself is being relocated) Introductory Overview An overview of the central valley from a natural perspective, overlaid with two prominent marks of human development, highways […]
Archive of posts filed under the Viz category.
One More Graph, SQL to R
import psycopg2 conn = psycopg2.connect( “dbname=example_db” ) curs = conn.cursor() tSQL = ”’ select emp_gden_min, res_units_gden_min, emp_gden_max, res_units_gden_max from p_translation_table; ”’ curs.execute( tSQL ) resT = curs.fetchall() from rpy2.robjects.packages import importr grdevices = importr( ‘grDevices’ ) grdevices.pdf(file=’/home/shared/aab.pdf’) r_plot_str = ”’ plot(c(0,1000),c(0,2000),type=”n”,log=”xy”,xlim=c(0.1,1000),ylim=c(0.1,2000), xlab=”employment”, ylab=”residence”) ”’ rpy2.robjects.r( r_plot_str ) tC = 0 for n in resT: tStr2 […]
Sacramento Vehicle Miles Travelled
early visualizations of a model written in Python and PostGIS, in 2011 at Calthorpe Associates, Berkeley. Lens on Daily Transportation PatternsSacramento, California
Extract and Sum Classified Areas by Grid Cell
Given a set of classified polygons, in this example classified into three categories by name, apply a reference grid, and sum the areas for each classification into float fields in a destination table. This code contains test harness pieces in it also, so that a smaller example can be executed and verified, before applying the […]
Early UrbanFootprint Grid Development
a few variations on grid visualization: