arthur-e

Overview

In general, it seems there are roughly five (5) ways to get "file data" (e.g. a GeoTIFF) out of a PostGIS geoprocessing workflow:

• Export just the raster field as an ASCII grid
• Connect to the database using a desktop client (e.g. QGIS) [1]
• Use a procedural language (like PLPGSQL or PLPYthon) [2]
• Use the COPY declaration to get a hex dump out and convert it to a binary file
• Fill a 2D NumPy array with a byte array and serialize it to a binary file using GDAL or psycopg2 [3, 4]
• Use ST_AsTiff() or the more general ST_AsGDALRaster() to get a byte array, which can be written to a binary file

skorasaurus

Changeset: A group of changes that you made to OSM data. Once uploaded to OSM, your edits are instantly available to others if they download OSM data. They may take a few minutes or several hours to appear on the map.

Extract: A large chunk of OSM data for a specific area (like a state, country, or geographic area).

Layer: A data source that's displayed on a slippy map (often is thought of as a group of tiles stitched together). (It also has another meaning in OSM, but don't worry about it right now).

Render: to convert from the OSM data into an image. Rendered data is a map.

Stylesheet: it means a text file of rules that define what features (like roads, buildings) are displayed, and how (what color should the road be ? How wide should be? What icon should be used for a restaurant?) on a map.

tmcw

import requests, os, glob, json

you = 'tmcw'
data = 'tweets'

try: os.mkdir(data)
except Exception: pass

def run(max_id = False):
    already = glob.glob("%s/*.json" % data)

gka

"""
Generator for packed circle cartograms
"""
import proj, gisutils

class Cartogram:

	def loadCSV(self, url, key='id', value='val', lon='lon', lat='lat'):
		import csv
		doc = csv.reader(open(url))

juniorz

# Some good references are:
# http://russbrooks.com/2010/11/25/install-postgresql-9-on-os-x
# http://www.paolocorti.net/2008/01/30/installing-postgis-on-ubuntu/
# http://postgis.refractions.net/documentation/manual-1.5/ch02.html#id2630392

#1. Install PostgreSQL postgis and postgres

brew install postgis
initdb /usr/local/var/postgres
pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log start