SaVi is satellite visualization software that lets you create, run, examine, and modify satellite orbits in two and three dimensions. Simulations of Iridium, Globalstar, Galileo, GPS, and other satellite constellations are included. SaVi requires Tcl and Tk on a system with Unix libraries. SaVi works well with the 3D renderer Geomview. Geomview is optional, though recommended for its 3D rendering capabilities.
geo-* is a set of tools for geocaching, including tools for accessing the www.geocaching.com, opencaching.com, opencaching.us, and navicache.com websites, tools for geocoding addresses and creating maps, and tools for manipulating Mapopolis place guide data. The focus of these tools is to provide a command line driven environment.
GRASS (the Geographic Resources Analysis Support System) is a software raster- and vector-based GIS (Geographic Information System), image processing system, graphics production system, and spatial modeling system. It contains many modules for raster data manipulation, vector data manipulation, rendering images on the monitor or paper, multispectral image geocoding and processing, point data management and general data management. It also has tools for interfacing with digitizers, scanners, and the PostgreSQL, DBF, and ODBC connected databases. GRASS operates on all common operating systems.
The GPSTk provides both fundamental and advanced GPS processing algorithms. A wide array of functions are provided by the library, notably RINEX I/O, ephemeris calculation, atmospheric refraction models, and positioning algorithms. GPSTk applications provide more concrete benefits to the user, including cycle slip detection and removal, calculation of the Total Electron Content (TEC) of the ionosphere, and RINEX file manipulation.
The NCAR Command Language (NCL) is a programming language designed specifically for the access, analysis, and visualization of data. It can be run in interactive or batch mode, and includes features common to modern languages, including types, variables, operators, expressions, conditional statements, loops, and functions and procedures, and also functions to handle the manipulation of metadata, the configuration of output graphics, the importing of data from a variety of formats, and an algebra that supports array operations. Many useful functions and procedures for processing and manipulating data are included.