GIS Basics

About this book

An abundance of literature exists that examines how organizations use GIS to solve problems, but until now there has been very little instructional material that details how the software performs these operations. GIS Basics introduces many of the main ideas and issues in the design of GIS, focusing on the technical issues relating to the inner workings of these systems. This textbook provides undergraduates with an introduction to supporting concepts in computer science, making much of the GIS literature much more accessible.

Based upon a series of articles that explained in simple language how computer science fundamentals apply to GIS, the text begins by considering the data structures and algorithms used to handle vector data. It then explores the way in which efficiency is addressed in practice, and describes the data structures and algorithms used for raster data. The text continues by discussing how large spatial databases can be indexed so that individual features can be accessed efficiently. The final chapters investigate geographical phenomena which can be modeled using both vector and raster, and compares the algorithms which are used in each case.

Contents

INTRODUCTIONHow Computers Solve ProblemsHow Computers Store Spatial Data: Vector and Raster Data ModelsStructure of the BookPseudo-CodeVECTOR DATA STRUCTURESStoring Points and LinesStoring Area BoundariesStoring Area Boundaries: The Topological ApproachSo What Is Topology?And How Does It Help? The Example of DIMEVECTOR ALGORITHMS FOR LINESSimple Line Intersection AlgorithmWhy the Simple Line Intersection Algorithm Won't Work: A Better AlgorithmDealing with Wiggly LinesCalculations on Lines: How Long is a Piece of String?VECTOR ALGORITHMS FOR AREASCalculations on Areas: Single PolygonsCalculations on Areas: Multiple PolygonsPoint in polygon: Simple AlgorithmaAnd Back to Topology for a Better AlgorithmTHE EFFICIENCY OF ALGORITHMSHow Is Algorithm Efficiency Measured?The Efficiency of the Line Intersection AlgorithmMore on Algorithm EfficiencyRASTER DATA STRUCTURESRaster Data Structures: The ArraySaving Space: Run Length Encoding and QuadtreesRASTER ALGORITHMSRaster Algorithms: Attribute Query for Run Length Encoded DataRaster Algorithms: Attribute Query for QuadtreesRaster Algorithms: Area CalculationsSPATIAL INDEXINGBinary Search TreeIndexing Data with a k-d TreeIndexing Vector Data Using a QuadtreeIndexing Raster Data Using Morton OrderDATA STRUCTURES FOR SURFACESData Models for SurfacesAlgorithms for Creating Grid Surface ModelsAlgorithms for Creating a Triangulated Irregular NetworkGrid Creation RevisitedALGORITHMS FOR SURFACESElevation, Slope and AspectHydrological Analysis Using a TINDetermining Flow Direction Using a Gridded DEMUsing the Flow Directions for Hydrological AnalysisDATA STRUCTURES AND ALGORITHMS FOR NETWORKSNetworks in Vector and RasterShortest Path AlgorithmData Structures for Network DataThe Travelling Salesman Problem

Customer Reviews

Biography

Stephen Wise became a lecturer in the Department of Geography at the University of Sheffield in 1990. He teaches GIS at both undergraduate and postgraduate levels. His research interests include the study of error propagation in digital terrain models, the development of spatial analysis facilities in GIS, and the use of image processing techniques to capture data from scanned maps.