SAGA GIS (System for Automated Geoscientific Analyses) is a free and open source geographic information system used for editing spatial data. It was developed by small team of Dept. of Physical Geography, University in Göttingen, Germany.

As the authors say: "SAGA is a hybrid GIS software. The first objective of SAGA is to give (geo-)scientists an effective but easy learnable platform for the implementation of geoscientific methods, which is achieved by SAGA's unique Application Programming Interface (API). The second is to make these methods accessible in a user friendly way. This is mainly done by the Graphical User Interface (GUI). Together this results in SAGA's true strength: a fast growing set of geoscientifc methods, bundled in exchangeable Module Libraries."

The standard modules are:

• File access: interfaces to various table, vector, image and grid file formats.
• Filter for grids: gaussian, laplacian, multi direction lee filter...
• Gridding: interpolation from vector data using triangulation, nearest neighbour, inverse distance...
• Geostatistics: residual analysis, ordinary and universal kriging, single and multiple regression analysis, variance analysis...
• Grid calculator: combine grids through user defined functions...
• Grid discretisation: skeletonisation, segmentation...
• Grid tools: merging, resampling, gaps filling...
• Image classification:cluster analysis, box classification, maximum likelihood, pattern recognition, region growing...
• Projections:various coordinate transformations for vector and grid data (using Proj4 and GeoTrans libraries), georeferencing of grids.
• Simulation of dynamic processes: TOPMODEL, nitrogen distributions, erosion, landscape development...
• Terrain analysis:slope, aspect, curvatures, curvature classification, analytical hillshading, sink eliminition, flow path analysis, catchment delineation, solar radiation, channel lines, relative altitudes...
• Vector tools: polygon intersection, contour lines from grid...
• And more...

SAGA is very strong and effective tool with user friendly GUI while only about 10 MB big. No installation needed.

Available for Windows and linux.

It can be used together with other GIS software like Kosmo to get better vector data and map producing capabilities.

External links

• SAGA GIS homepage

es:SAGA GIS