Michael Ewald lx-88

layout

title

description

Purpose

PostgreSQL & PostGIS Cheatsheet

This is a collection of information on PostgreSQL and PostGIS for what I tend to use most often.

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

	'use strict';

	process.env.NODE_TLS_REJECT_UNAUTHORIZED = '0';

	var localtunnel = require('localtunnel');
	var request = require('request');

	var qs = require('querystring');
	var url = require('url');
	var http = require('http');

	#!/usr/bin/env python
	"""
	Example of using Keras to implement a 1D convolutional neural network (CNN) for timeseries prediction.
	"""

	from __future__ import print_function, division

	import numpy as np
	from keras.layers import Convolution1D, Dense, MaxPooling1D, Flatten
	from keras.models import Sequential

	import akka.actor._
	import akka.stream.scaladsl.Flow
	import org.apache.spark.streaming.dstream.ReceiverInputDStream
	import org.apache.spark.streaming.receiver.ActorHelper
	import akka.actor.{ ExtensionKey, Extension, ExtendedActorSystem }

	import scala.reflect.ClassTag

	object AkkaStreamSparkIntegration {

	import matplotlib.pyplot as plt
	import numpy as np

	from shapely.geometry import LineString
	from shapely.ops import triangulate

	def uniform_sample(poly, n=100):
	"""
	Uniformly sample the Delaunay triangulation of a polygon. If the polygon
	is convex, this will uniformly sample its area.

	---
	version: 1
	disable_existing_loggers: False
	formatters:
	simple:
	format: "%(name)-20s%(levelname)-8s%(message)s"
	handlers:
	console:
	class: logging.StreamHandler
	level: DEBUG

	### Important note: I'm no longer maintaining this gist, since this code is incorporated into the
	### VulnToolkit package.
	### Because it's not being maintained, the code below might not work. The latest, updated version
	### is available at https://github.com/troyhill/VulnToolkit/blob/master/R/HL.r



	### Function to pick out high and low tides from a dataset of tidal water levels
	###
	### Arguments:

	#!/usr/bin/env python

	import wx
	from wx import EVT_CLOSE
	import wx.grid as gridlib

	EVEN_ROW_COLOUR = '#CCE6FF'
	GRID_LINE_COLOUR = '#ccc'

	class PandasTable(wx.Frame):

Michael Ewald lx-88

Purpose

PostgreSQL & PostGIS Cheatsheet

TOC

Processing LiDAR to extract building heights

Walk through