is an
Open Source ,
Free Software Geographical Information System (GIS) with
Raster ,
Topological Vector ,
Image Processing , and
Graphics production functionality that operates on various
Platforms through a
Graphical User Interface and
Shell in the
X Window System . It is released under
GNU General Public License (GPL).
The recent GRASS 6 release introduces a new topological 2D/3D vector engine and support for
Vector Network Analysis . Attributes are managed in
''.dbf'' files or
SQL -based
DBMS such as
MySQL ,
PostgreSQL /
PostGIS , and
SQLite . The system is capable of visualizing
3D Vector Graphics data and
Voxel volumes. GRASS supports an extensive range of raster and vector formats through the binding to
GDAL/OGR Libraries , including OGC-conformal (
Open Geospatial Consortium )
Simple Features for
Interoperability with other GIS. It also supports
Linear Reference System .
The GRASS Development Team is a multi-national group consisting of developers at numerous locations. GRASS is one of the eight initial Software Projects of the
Open Source Geospatial Foundation .
GRASS supports raster and vector data in two and three dimensions. The vector data model is
Topological , meaning that areas are defined by boundaries and centroids; boundaries cannot overlap within a single layer. This is in contrast with OpenGIS
Simple Features , which define vectors more freely, much as a non-georeferenced vector illustration program does.
GRASS is designed as an environment in which tools that perform specific GIS computations are executed. Unlike typical
Application Software , upon starting GRASS, the user is presented with a UNIX shell containing a modified environment that supports the execution of GRASS commands (known as modules). The environment has a state that includes such parameters as the geographic region covered and the
Map Projection in use. All GRASS modules read this state and additionally are given specific parameters (such as input and output maps, or values to use in a computation) when executed. The majority of GRASS modules and capabilities can be operated via a graphical user interface (provided by a GRASS module), as an alternative to manipulating geographic data in shell. There are over 200 core GRASS modules included in the GRASS distribution, and over 100 add-on modules created by users and offered on the GRASS web site. The GRASS libraries and core modules are written in
C ; other modules are written in C, UNIX shell,
Tcl , or other scripting languages. The GRASS modules are designed under the
Unix Philosophy and hence can be combined using shell scripting to create more complex or specialized modules by a user without knowledge of C programming.
There is cooperation between GRASS and
Quantum GIS (QGIS). Recent versions of QGIS can be executed within the GRASS environment, allowing QGIS to be used as a user-friendly graphical interface to GRASS that more closely resembles other graphical GIS software than does the unique shell-based GRASS interface. See the screenshot for an example.
There also exists a project to re-implement GRASS in
Java as
JGRASS .
GRASS (Geographic Resources Analysis Support System) GRASS has been under continuous development since 1982 and has involved a large number of federal US agencies, universities, and private companies. The core components of GRASS and the management of the integration efforts into GRASS releases were accomplished by the U.S. Army - Construction Engineering Research Laboratory (USA-CERL) in Champaign, Illinois. USA-CERL completed its last release of GRASS as version 4.1 in 1992, and provided five updates and patches to this release through 1995. USA-CERL also wrote the core components of the GRASS 5.0 floating point version.
The development of GRASS was begun by the U.S. Army Corp of Engineering Research Laboratory (USA-CERL) in
Champaign, Illinois , a branch of the
U.S. Army Corps Of Engineers to meet the need of the United States military for software for
Land Management and
Environmental Planning .
An key motivation was the
National Environmental Policy Act . The development platform was
UNIX running on
VAX hardware. During 1982 through 1995, USA-CERL led the development of GRASS, with the involvement of numerous others, including universities and other federal agencies. USA-CERL officially ceased its involvement in GRASS after release 4.1 (1995), though development had been limited to minor patches since 1993. A group formed at
Baylor University to take over the software, releasing GRASS 4.2. Around this period, the license of the originally public-domain GRASS software was changed to the GNU GPL and a port of the software to
Linux was made. In 1998,
Markus Neteler , the current project leader, announced the release of GRASS 4.2.1, which offered major improvements including a new
Graphical User Interface .GRASS Developent Team. ''
GRASS History ''. Retrieved on 2007-07-11.
Subsequently, GRASS has evolved into a powerful software suite with a wide range of applications in many different areas of
Scientific Research .
GRASS is currently used in academic and commercial settings around the world, as well as many governmental agencies including
NASA ,
NOAA ,
USDA ,
DLR ,
CSIRO , the
National Park Service , the
U.S. Census Bureau ,
USGS , and many
Environmental Consulting companies.
GRASS development is split into a stable branch (6.2) and a development branch (6.3). The stable branch is recommended for most users, while the 6.3 branch operates as a testbed for new features.
- Neteler, M. and H. Mitasova "Open Source GIS: A GRASS GIS Approach. Second Edition." Boston: Kluwer Academic Publishers/Springer. 424pp, 2004. ISBN
1-4020-8064-6, Online Supplement
- GDF Hannover bR: GRASS GIS 6.0 Tutorial, Version 1.2, 2005, Online Supplement
- ''Indian Example'' PDF download {Link without Title}
- A.P. Pradeepkumar (2003) "Absolute Beginners Guide to Linux/GRASS installation" Online publication at GRASS Development Project Website In English available at http://grass.itc.it/gdp/tutorial/abs_beginners.pdf
- 原著 A. P. Pradeepkumar (2003) GRASS 5.00 安装新手指南 in Chinese available at http://www.cngis.org/archive/opensource/attach/GRASS%205%20%B0%B2%D7%B0%D0%C2%CA%D6%D6%B8%C4%CF.pdf
