extract

pylayers.gis.osmparser.extract(alat, alon, fileosm, fileout)

extraction of an osm sub region using osmconvert

alat : array of latitude (1xn) alon : array of longitude (1xn) fileosm : source osm file filout : output osm file

m : Basemap oject for coordinates conversion

This function takes two (1xn) arrays of latitude an longitude values Calculates extrema of those values. Invokes osmconvert script on a source fileosm and extract the corresponding zone in the fileout file.

The functions returns a basemap object for coordinates conversion on this file.