Learning Geospatial Analysis with Python - Second Edition

394 Pages·2015·14.264 MB·English

by  Joel Lawhead

Learning Geospatial Analysis
with Python
Second Edition
An effective guide to geographic information system
and remote sensing analysis using Python 3
Joel Lawhead
BIRMINGHAM - MUMBAI
Learning Geospatial Analysis with Python
Second Edition
Copyright © 2015 Packt Publishing
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First published: October 2013
Second edition: December 2015
Production reference: 1211215
Published by Packt Publishing Ltd.
Livery Place
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Birmingham B3 2PB, UK.
ISBN 978-1-78355-242-9
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Credits
Author Project Coordinator
Joel Lawhead Izzat Contractor
Reviewers Proofreader
Mark Cederholm Safis Editing
Truc Viet Le
John Maurer Indexer
Mariammal Chettiyar
Julia Wood
Graphics
Commissioning Editor
Jason Monteiro
Kartikey Pandey
Production Coordinator
Acquisition Editors
Arvindkumar Gupta
Kevin Colaco
Usha Iyer
Cover Work
Kartikey Pandey
Arvindkumar Gupta
Content Development Editor
Anish Sukumaran
Technical Editor
Manthan Raja
Copy Editor
Tasneem Fatehi
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About the Author
Joel Lawhead is a project management institute-certified Project Management
Professional (PMP), certified GIS Professional (GISP), and the Chief Information
Officer (CIO) of NVision Solutions Inc., an award-winning firm that specializes in
geospatial technology integration and sensor engineering.
Joel began using Python in 1997 and started combining it with geospatial software
development in 2000. He is the author of the first edition of Learning Geospatial
Analysis with Python and QGIS Python Programming Cookbook, both by Packt
Publishing. His Python cookbook recipes were featured in two editions of Python
Cookbook, O'Reilly Media. He is also the developer of the widely-used, open source
Python Shapefile Library (PyShp). He maintains the geospatial technical blog
http://geospatialpython.com/ and the Twitter feed, @SpatialPython, which
discusses the use of the Python programming language in the geospatial industry.
In 2011, Joel reverse-engineered and published the undocumented shapefile spatial
indexing format and assisted fellow geospatial Python developer, Marc Pfister,
in reversing the algorithm used, allowing developers around the world to create
better-integrated and more robust geospatial applications.
Joel serves as the lead architect, project manager, and co-developer for geospatial
applications used by U.S. government agencies, including NASA, FEMA, NOAA,
the U.S. Navy, and many other commercial and non-profit organizations. In 2002,
he received the international Esri Special Achievement in GIS award for his work
on the Real-Time Emergency Action Coordination Tool (REACT), for emergency
management using geospatial analysis.
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About the Reviewers
Mark Cederholm, GISP, has over 20 years of experience in developing GIS
applications using various Esri technologies, from ARC/INFO AML to ArcObjects
to ArcGIS Runtime and Web SDKs. He lives in Flagstaff, Arizona.
He has been a technical reviewer for the book, Developing Mobile Web ArcGIS
Applications, Packt Publishing.
Truc Viet Le is currently a PhD candidate in information systems at the
Singapore Management University. His research interests primarily involve
novel methods for the modeling and predicting of human mobility patterns and
trajectories, learning smart strategies for urban transportation, and traffic flow
prediction from fine-grained GPS and sensor network data. He uses R and Python
every day for his work, where he finds R superb for data manipulation/visualization
and Python an ideal environment for machine learning tasks. He is also interested
in applying data science for the social work and international development work.
When not behind the computer screen, he is an avid traveler, adventurer, and an
aspiring travel writer and photographer. His work portfolio and some of his writings
can be found on his personal website at http://vietletruc.com/.
He spent a wonderful year at Carnegie Mellon University in Pittsburgh,
Pennsylvania, while pursuing his PhD. Previously, he obtained his bachelor's and
master's degrees from Nanyang Technological University in computer engineering
and mathematical sciences.
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John Maurer is a programmer and data manager at the Pacific Islands Ocean
Observing System (PacIOOS) in Honolulu, Hawaii. He creates and configures
web interfaces and data services to provide access, visualization, and mapping of
oceanographic data from a variety of sources, including satellite remote sensing,
forecast models, GIS layers, and in situ observations (buoys, sensors, shark tracking,
and so on) throughout the insular Pacific. He obtained a graduate certificate in
remote sensing as well as a master's degree in geography from the University of
Colorado, Boulder, where he developed software to analyze ground-penetrating
radar (GPR) for snow accumulation measurements on the Greenland ice sheet. While
in Boulder, he worked with the National Snow and Ice Data Center (NSIDC) for
eight years, sparking his initial interest in Earth science and all things geospatial: an
unexpected but comfortable detour from his undergraduate degree in music, science,
and technology at Stanford University.
Julia Wood is currently a Geospatial Information Sciences (GIS) analyst who
spends her professional time completing projects as a contractor in the Washington
D.C. area. She graduated magna cum laude from the University of Mary Washington
in Fredericksburg, Virginia, in the spring of 2014 with a bachelor's degree in both
history and geography as well as a minor in GIS. Though her career is still in its early
stages, Julia has aspirations to keep growing her skill set, and working on this review
has certainly helped expand her professional experience; she hopes to continue
learning and eventually work toward a master's degree while still working full time.
In her non-work life, she enjoys reading, crafting, cooking, and exploring the big city,
one local restaurant at a time.
Reviewing this book for Packt Publishing was Julia's first professional reviewing
experience and she hopes that she can pursue similar endeavors in the future.
I'd like to thank my parents, John and Diana, for always encouraging
me to do well in my educational and professional endeavors; my
sister, Sarrina, and my brother, Jonathan, for offering support
and advice when I needed it; and my boyfriend, Max, and my cat,
Coco, for keeping me company while I conducted the reviews
for this book. A thank you to Packt for letting me be a part of this
experience!
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Table of Contents
Preface ix
Chapter 1: Learning Geospatial Analysis with Python 1
Geospatial analysis and our world 1
Beyond disasters 4
History of geospatial analysis 4
Geographic information systems 9
Remote sensing 11
Elevation data 17
Computer-aided drafting 18
Geospatial analysis and computer programming 18
Object-oriented programming for geospatial analysis 19
Importance of geospatial analysis 21
Geographic information system concepts 21
Thematic maps 22
Spatial databases 23
Spatial indexing 24
Metadata 24
Map projections 24
Rendering 26
Remote sensing concepts 27
Images as data 27
Remote sensing and color 28
Common vector GIS concepts 28
Data structures 28
Buffer 30
Dissolve 30
Generalize 31
Intersection 32
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