wboykinm

In case anyone is interested, I've been trying to use turf.js on both Mapbox and Mapzen vector tiles, and I've learned a few things I wish I'd known going in.

Background

This thing I've been working on for a month or so here and there, to make maps like this:

Purpose

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

YKCzoli

Processing LiDAR to extract building heights

Walk through

Detailed walk through of building extraction using postgis

First lets pull a data layer from of openstreetmap. You can do this any which way you’d like, as there are a variety of methods for pulling openstreetmap data from their database. Check the [wiki] (http://wiki.openstreetmap.org/wiki/Downloading_data) for a comprehensive list. My favourite method thus far is pulling the data straight into QGIS using the open layers plugin. For those who may want to explore this method, check [this tutorial] (http://www.qgistutorials.com/en/docs/downloading_osm_data.html). For building extraction you only need building footprints, and include the building tags. Not all polygons are of type building in OSM, so we can download all the polygons, and then filter the layer for only polygons tagged as buildings.

LiDAR data was pulled from USGS via the Earth Explorer site. [Here] (http://earthobservatory.nasa.gov/blogs/ele

rgdonohue

This Python script utilizes the GeoPy geocoding library to batch geocode a number of addresses, using various services until a pair of latitude/longitude values are returned.

https://gist.github.com/rgdonohue/c4beedd3ca47d29aef01

tmcw

This is a non-technical reading list for technical people.

• How to Program Independent Games
• Kill Math (and Don't Kill Math)
• Move Fast and Don't Break Things
• Launch & The Web Is a Customer Service Medium by Paul Ford
• _why at Art & Code
• Repetitive Process

This is a list of software you should read like a novel.

meetar

##How to get started contributing to a Humanitarian OpenStreetMap Team task

###Overview

OpenStreetMap (OSM) is an open-source map of the world that anyone can edit. But like any map, it's incomplete.

The Humanitarian OpenStreetMap Team (HOT) helps organize people to improve the OSM map for crisis areas, mostly so aid workers can find their way around and make decisions about undermapped places. The data in these crisis areas is often very poor, or completely non-existent. Therefore any contribution you make at all will be a vast improvement, and could materially help people who are on the ground right now, looking at this data as you edit it, and deciding where to go and who to help.

There are many HOT tasks active at once. As of August 2014, the highest-priority tasks are Gaza and areas affected by the West African Ebola outbreak.

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

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))

clhenrick

Cartographic Design Resources

by Chris Henrick

Tools

• Color Brewer: Tool created by Cynthia Brewer that offers advice for using color on maps, specifically with thematic mapping. Lets you export color schemes to various formats.

• Mapshaper for generalizing your geospatial data which helps your maps not only look better but load faster. Mapshaper let's you preview how generalized it looks before you export it.

Guides & Tutorials

• Nathaniel Kelso's Geo How To wiki though now a little out dated still has lots of great info in it.

fitnr

states = fl la nc ok va \
al ga ma nd or vt \
ar hi md ne pa wa \
az ia me nh ri wi \
ca id mi nj sc wv \
co il mn nm sd wy \
ct in mo nv tn \
dc ks ms ny tx \
de ky mt oh ut