Introduction to the GRASS User's Reference Manual

Background

This reference manual details the use of programs distributed with Geographical Resources Analysis Support System (GRASS), a public domain, image processing and geographic information system (GIS) originally developed by researchers in the Environmental Division of the US Army Construction Engineering Research Laboratories in Champaign, Illinois, with enhancements and support now performed by the GRASS Research Group at Baylor University.

The GRASS system is used to input, manipulate, analyze, and output geographic data by users in both military and nonmilitary, public and private agencies based in North America, Europe, and other parts of the world.

Although most GRASS development has been conducted at USACERL, system integration, development, testing, distribution, training, and support are performed by numerous publicly and privately operated sites throughout the world. Recently, the GRASS Research Group at Baylor University took on the task of updating GRASS to version 4.2 and enhancing the documentation.

The GRASS Development Team has further developed the GRASS GIS by producing GRASS 5.x, a floating-point version of the GRASS GIS. Reference Manual

The manual explains the capabilities, syntax, and use of current GRASS programs. Chapters contain program entries which are ordered alphabetically by program name. Each entry contains:

• the program name

• a brief description

• the version of GRASS associated with the module

• a synopsis of files associated with the program

• a full description of the program's capabilities and uses

• a summary of the command-line operations associated with the program

• a list of associated or related programs

• a list of program authors

Throughout the manual, program input to be explicitly entered by the user is printed in bold text. User-specified input (i.e., variables set by the user) is set in italic type. Boxed text shows information output to the user's terminal screen.

GRASS Categories

The GRASS code has been divided into the following categories according to application:

• Display Commands

• General Commands

• Imagery Commands

• Miscellaneous Management Commands

• Paint Commands

• Photo Commands

• PostScript Commands

• Raster Commands

• Shell Scripts

• Sites Commands

• Vector Commands