Describes several useful paradigms for the design and implementation of efficient external memory (EM) algorithms and data structures. The problem domains considered include sorting, permuting, FFT, scientific computing, computational geometry, graphs, databases, geographic information systems, and text and string processing.

The algorithms involve using techniques from computer science and mathematics to solve combinatorial problems whose associated data require the use of a hierarchy of storage devices. The 15 papers discuss such topics as synopsis data structures for massive data sets, maximum clique problems in very large graphs, concrete software libraries, computing on data streams, efficient cross-trees for external memory, efficient schemes for distributing data on parallel memory systems, and external memory techniques for iso-surface extraction in scientific visualization. Annotation copyrighted by Book News, Inc., Portland, OR.

Geographical Information Systems (GIS) are computer systems for storing, displaying and analyzing spatial data. The past twenty years have seen a rapid growth in their use in government, commerce and academia, and they can be used for managing a network of utilities, from handling census data through to planning the location of a new supermarket. But how do they work? Stephen Wise has been a regular contributor to GeoEurope and his 'Back to Basics' articles have provided a clear and simple introduction to the inner workings of GIS for a non-specialist audience. He now presents the original articles with new material and provides a new coverage of both major types of GIS: vector and raster systems. Undergraduates and professionals who wish to improve their knowledge of GIS should get a better understanding of how GIS operate in the way that they do, such as how spatial data is stored on a computer, how the different methods affect the capabilities of the GIS, how basic operations performed and how the choice of algorithm affects the speed of the system.