181 lines
3.9 KiB
HTML
181 lines
3.9 KiB
HTML
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>What Is GRASS?</TITLE
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NAME="WHATISGRASS"
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>2. What Is GRASS?</A
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><P
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> GRASS (Geographic Resources Analysis Support System) is a public domain
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raster based GIS, vector GIS, image processing system, and graphics
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production system. Created by the US Army Corps of Engineers,
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Constriction Engineering Research Laboratory (USA/CERL) and enhanced by
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many others, it is used extensively at government offices, universities
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and commercial organizations throughout the world. It is written mostly
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in C for various UNIX based machines. Linux is one of its more robust
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implementations.
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</P
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> GRASS contains over 40 programs to render images on monitor and paper;
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over 60 raster manipulation programs; over 30 vector manipulation
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programs; nearly 30 multi-spectral image processing manipulation
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programs; 16 data management programs; and 6 point file management
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programs.
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</P
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><P
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> GRASS' strengths lie in several fields. The simple user interface makes
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it an ideal platform for those learning about GIS for the first time.
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Users wishing to write their own code can do so by examining existing
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source code, interfacing with the documented GIS libraries, and by using
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the GRASS Programmers' Manual. This allows more sophisticated
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functionality to be fully integrated within GRASS.
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</P
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> Other strengths include GRASS' pioneering of mixed resolutions in a data
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base, mixed geographic coverage areas in a data base, raster image
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compression techniques via run-length encoding and reclassification
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lookup tables, GRASS' rescaling of display images on the fly to fill the
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display screen, plus its fundamental design criterion of powerful
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computer-assisted scientific analysis of environmental issues (as
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opposed to merely going for intricate cartographic output of relatively
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simple processes).
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</P
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><P
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> GRASS is usually supplied as free, non-copyright source code to be
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compiled on host machines. Some compiled binaries are also easily
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obtainable at no cost via the Internet. It runs on a variety of UNIX
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platforms.
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</P
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><P
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> Copied from Project Assist
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<A
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HREF="http://www.geog.le.ac.uk/assist/grass"
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TARGET="_top"
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><I
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CLASS="CITETITLE"
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>Intro to GRASS</I
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></A
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>.
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>What is a GIS?</TD
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> </TD
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><TD
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>A Brief History of GRASS</TD
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