SEXTANTE Project
SEXTANTE is a set of free geospatial analysis tools. The main aim of SEXTANTE is to create a platform for the development of geoalgorithms that makes it easy both to implement and to use those algorithms.
"A GIS project launched in 2004 with the main goal of developing a GIS solution specially designed for the needs of regional government foresters. Though it was originally targeted at professional of forest management, it has proved to be an all purpose solution suitable for any user in need of strong geospatial analysis capabilities, and it is developed as such nowadays. Additional elements for forest inventory are being developed as well within the project, but they are not included in this website." [from Website]
SEXTANTE (Sistema Extremeno de Analisis Territorial) tools (>200), graphic modeler, and command-line interface work with gvSIG open source GIS and will become a standard release component of gvSIG v2.0. SEXTANTE is free software and is distributed under the GPL license.
Here is a list of the geoanalysis algorithms currently available in SEXTANTE:
- Analysis tools for raster layers
- Analytical Hierarchy Process (AHP).
- Change Vector Analysis.
- Ordered Weighted Average (OWA).
- Predictive models.
- ROC Curve.
- Soft classification
- Supervised Classification
- Unsupervised classification (clustering).
- Basic hydrological analysis
- A simple hydrological model.
- Channel network.
- Creature synthetic hyetograph.
- Flow accumulation.
- Geomorphological instantaneous Unit Hydrograph.
- Sink filling.
- Time to outlet.
- Upslope area from outlet zone.
- Upslope area from a single point.
- Watersheds.
- Basic tools for raster layers
- Aggregate.
- Basic statistics.
- Change data type.
- Complete grid.
- Correlation between layers.
- Crop grid with polygon layer.
- Crop to valid data cells.
- Gradient lines.
- Histogram.
- Invert mask.
- Merge grids.
- Mirror/flip.
- Normalize.
- Sort.
- User-defined 3 X 3 filter.
- Void filling.
- Void filling (nearest neighbour).
- Volume calculation. .
- Volumen between two layers.
- Raster buffers
- Buffer.
- Threshold buffer.
- Calculus tools for raster layer
- Raster calculator.
- Cost, distances and routes
- Accumulated cost (anisotropic).
- Accumulated cost (combined).
- Accumulated cost (isotropic).
- Cost in predefined routes.
- Cost in predefined routes (anisotropic).
- Generate alternative routes.
- Least cost path.
- Polar to rect.
- Rect to polar.
- Sum of cost to all points.
- Focal statistics
- Equal values count.
- Kurtosis (neighbourhood).
- Larger values count (neighbourhood).
- Lower values count (neighbourhood).
- Maximum (neighbourhood)
- Mayority (neighbourhood)
- Mean (neighbourhood)
- Median (neighbourhood).
- Minimum (neighbourhood).
- Minority (neighbourhood).
- Radius of variance.
- Range (neighbourhood).
- Skeweness (neighbourhood).
- Variance (neighbourhood).
- Fuzzy logic
- Fuzzify.
- Geomorphometry and terrain analysis
- Anisotropic coefficient of variation.
- Aspect.
- Convergence index.
- Curvatures.
- Elevation-relief ratio.
- Hypsometry.
- Landform classification.
- Protection index.
- Real area.
- Slope.
- Geostatistics
- Semivariances (raster).
- Image processing
- Calibrate an image.
- Calibrate an image (regression).
- Contrast stretching.
- Detect and vectorize individual trees.
- Equalize.
- Erosion/Dilation.
- HIS -> RGB.
- RGB -> HIS.
- Thinning.
- Indices and other hydrological parameters
- C factor from NDVI.
- Distance to channel network.
- Edge contamination.
- Elevation over channel network.
- Max. value uphill.
- Mean value uphill.
- Net Balance.
- Slope length.
- Strahler Order.
- Topographic indices.
- Local statistics
- Equal values count.
- Kurtosis.
- Larger values count.
- Lower values count.
- Maximum.
- Maximum value layer.
- Mayority.
- Mean.
- Median.
- Minimum.
- Minimum value layer.
- Minority.
- Range.
- Skewness.
- Variance.
- Location/allocation
- Location/allocation.
- Pattern analysis
- Diversity.
- Dominace.
- Fragmentation. .
- Number of different classes.
- Profiles
- Cross sections.
- Flow line profile.
- Profile.
- Raster creation tools
- Constant grid.
- Grid from function.
- Random DEM.
- Random grid (Bernoulli).
- Random grid (normal).
- Random grid (uniform).
- Rasterizacion and interpolation
- Density.
- Density (kernel).
- Inverse Distance Weighting (IDW).
- Kriging.
- Linear decrease.
- Nearest neighbour.
- Rasterize vector layer.
- Universal Kriging.
- Reclassify raster layers
- Divide in n classes of equal amplitude.
- Divide in n classes of equal area.
- Reclassify.
- Reclassify in disjoint classes.
- Reclassify in ordered classes.
- Statistical methods
- Bernoulli probability distribution.
- Chi squared probability distribution.
- Covariance matrix.
- Exponencial probability distribution.
- Multiple regression.
- Normal probability distribution.
- Principal Components Analysis.
- Regression.
- Student's probability distribution.
- Table tools
- Basic statistics.
- Correlation between fields.
- Save as CSV.
- Tools for categorical raster layers
- Aggregation index.
- Class statistics.
- Combine grids.
- Cross checking(Kappa index).
- Filter clumps.
- Fragstats (area/density/edge metrics).
- Fragstats (diversity metrics).
- Grids from table and classified grid.
- Tools for line layers
- Change line direction.
- Directional mean.
- Lines to equispaced points.
- Polylines to polygons.
- Simplify lines
- Sinuosity.
- Split lines with points layer.
- Tools for point layers
- Distance matrix.
- Mean center and standard distance.
- Median center.
- Minimum enclosing shapes.
- Nearest neighbour analysis.
- Points layer from table.
- Quadrant analysis.
- Ripley's K.
- Sample raster layers.
- Snap points to layer.
- Spatial autocorrelation.
- Spatial cluster.
- Tools for polygon layers
- Centroids.
- Count points in polygons.
- Geometric properties of polygons.
- Grid statistics in polygons.
- Point statistics in polygons.
- Polygons to polylines.
- Tools for vector layers
- Adjust n point polygon.
- Basic statistics.
- Buffer.
- Cluster.
- Correlation between fields.
- Clip. Th
- Create graticule.
- Field calculator.
- Merge.
- Disolve
- Union
- Difference
- Intersection
- Transform.
- Vectorization
- Contour lines.
- Raster layer to points layer. T
- Vectorize raster layer (lines).
- Vectorize raster layer (polygons).
- Vegatation indices
- CTVI.
- NDVI.
- NRVI.
- PVI(Perry and Lautenschlager).
- PVI(Qi et al).
- PVI(Richardson and Wiegand).
- PVI(Walther and Shabaani).
- TTVI.
- TVI.
- Visibility and lighting
- Horizon blockage.
- Line of sight.
- Shaded relief.
- Solar radiation.
- Visibility.
- Visual exposure.
GIS/Mapping, Computer Applications and Data
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