PostGIS database contains several geometry (polyline) tables (with names "D1_r", "D2_r", "D3_r"). I calculate length for one "postgis layer" use request: SELECT ...
I was quite unsatisfied with Calculating Length of Linestrings in WGS84 in Miles. It kept me wondering if there is a more convenient, Pythonic way to calculate the length of a WKT linestring according ...
In postgis 1.5 for the below given query the answer is 1540651.62674101 meters , SELECT ST_Length(ST_GeomFromText('LINESTRING(77.83042478941326 9.98463896136159,78.03469506809812 23.90398909552571 ...
Online calculators such as http://www.csgnetwork.com/degreelenllavcalc.html (view page source) use the below formulas to get meters per degree. I understand in general how distance per degree varies ...
I am working on Safe Routes to School, and have created a network dataset. Each segment of the newtork has a 'walk_score' assinged (0,1,3,5,10), based upon street classification and sidwalk ...