Matthew Perry perrygeo

Geospatial Data Engineer, using ML and Remote Sensing to build high-quality forest carbon credits @pachama

perrygeo / nearest_features.py

Created April 25, 2012 21:51

Find the nearest point features in a shapefile to a given coordinate

	import numpy as np
	from scipy.spatial import KDTree
	from fiona import collection

	def nearest_features(datasource, x, y, n=1):
	"""
	datasource: The ogr datasource path
	x, y: coordinates to query for nearest
	n: number of features (default = 1 or the single nearest feature)

perrygeo / gist:2514255

Created April 27, 2012 23:24

Global search and replace

	#Global search and replace:
	grep -lr -e 'oldtext' * \| xargs sed -i 's/oldtext/newtext/g'

perrygeo / gist:2560058

Created April 30, 2012 17:07

Static files watcher

	# courtesy of @eknuth
	# Watches for media changes and runs the install_media command (equivalent of collectstatic)

	while true
	do
	inotifywait -r -e modify -e move -e create -e delete ../media ~/proj/env/src/madrona/media/ \| while read line
	do
	python manage.py install_media
	done
	done

perrygeo / gist:2770615

Created May 22, 2012 18:03

FGDC in pycsw

Set up the cfg file with

profiles=apiso,fgdc

and intialized the database

python sbin/pycsw-admin.py -c setup_db -f default.cfg

perrygeo / map.html

Created May 24, 2012 19:00

CartoDB with UTFGrid in Openlayers, example

	<!DOCTYPE html>
	<html>
	<head>
	<title>CartoDB/OpenLayers Demo</title>
	<link rel="stylesheet" href="http://openlayers.org/dev/theme/default/style.css" type="text/css">
	<style>
	html, body {
	width: 100%;
	height: 100%;
	}

perrygeo / mperry_jqplot_line.html

Created August 30, 2012 19:57

JQPlot line chart example


	<!DOCTYPE html>
	<html>
	<head>
	<title>mperry Line Charts</title>
	<link class="include" rel="stylesheet" type="text/css" href="../jquery.jqplot.min.css" />
	<!--[if lt IE 9]><script language="javascript" type="text/javascript" src="../excanvas.js"></script><![endif]-->
	<script class="include" type="text/javascript" src="../jquery.min.js"></script>
	<script class="include" type="text/javascript" src="../jquery.jqplot.min.js"></script>
	<script class="include" type="text/javascript" src="../plugins/jqplot.canvasTextRenderer.min.js"></script>

perrygeo / mercator_scale.py

Last active February 17, 2023 08:10

Web Mercator Scale/Resolution Calculations

	"""
	Web Mercator Scale and Resolution Calculations
	Python implementation of the formulas at http://msdn.microsoft.com/en-us/library/bb259689.aspx
	"""
	import math

	def meters_per_pixel(zoom, lat):
	"""
	ground resolution = cos(latitude * pi/180) * earth circumference / map width
	"""

perrygeo / normalize_numpy.py

Created January 11, 2013 17:10

Normalize a 2D numpy array so that each "column" is on the same scale (Linear stretch from lowest value = 0 to highest value = 100)

	import numpy as np

	rawpoints = np.array(
	[[2500, 0.15, 12],
	[1200, 0.65, 20],
	[6200, 0.35, 19]]
	)

	# Scale the rawpoints array so that each "column" is
	# normalized to the same scale

perrygeo / pubsub_server.py

Last active March 17, 2018 10:43

Runs a simple pubsub listener which pushes to clients via sockjs

	# -- coding: utf-8 --
	"""
	Runs a simple pubsub listener which pushes to clients via sockjs
	Based on https://gist.github.com/mrjoes/3284402

	Eventually I'd like to have one redis connection listening on user_* channel
	and pushing messages ONLY to that user's client. Currently it just sends
	a message to everyone.

	Setup:

perrygeo / __Esri_Unions

Last active December 16, 2018 16:23

Create ArcGIS-style Union and Identity non-overlapping polygon layers

	Create ArcGIS-style Union and Identity non-overlapping polygon layers
	from multiple input polygon tables (potentially overlapping) while retaining original attributes.

	http://webhelp.esri.com/arcgisdesktop/9.2/index.cfm?TopicName=Union_(Analysis)
	http://webhelp.esri.com/arcgisdesktop/9.2/index.cfm?TopicName=identity_(analysis)
	http://gis.stackexchange.com/questions/83/separate-polygons-based-on-intersection-using-postgis/121