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raster commands: r.average Finds the average of values in a cover map within areas assigned the same category value in a user-specified base map. r.basins.fill Generates a raster map layer showing watershed subbasins. r.bilinear Bilinear interpolation utility for raster map layers. r.blend Blends color components of 2 raster maps by a given % first map' r.buffer Creates a raster map layer showing buffer zones surrounding cells that contain non-NULL category values. r.cats Prints category values and labels associated with user-specified raster map layers. r.circle Creates a raster map containing concentric rings around a given point. r.clump Recategorizes data in a raster map layer by grouping cells that form physically discrete areas into unique categories. r.coin Tabulates the mutual occurrence (coincidence) of categories for two raster map layers. r.colors Creates/Modifies the color table associated with a raster map layer. r.composite Combines red, green and blue map layers into a single composite map layer. r.compress Compresses and decompresses raster files. r.contour Produces a GRASS binary vector map of specified contours from GRASS raster map layer. r.cost Outputs a raster map layer showing the cumulative cost of moving between different geographic locations on an input raster map layer whose cell category values represent cost. r.covar Outputs a covariance/correlation matrix for user-specified raster map layer(s). r.cross Creates a cross product of the category values from multiple raster map layers. r.describe Prints terse list of category values found in a raster map layer. r.digit r.digit r.distance Locates the closest points between objects in two raster maps. r.drain Traces a flow through an elevation model on a raster map layer. r.fill.dir Filters and generates a depressionless elevation map and a flow direction map from a given elevation layer r.fillnulls Fills no-data areas in raster maps using v.surf.rst splines interpolation r.flow Construction of slope curves (flowlines), flowpath lengths, and flowline densities (upslope areas) from a raster digital elevation model(DEM). r.grow Generates a raster map layerwith contiguous areas grown by one cell. r.his Generates red, green and blue raster map layers combining hue, intensity, and saturation (his) values from user-specified input raster map layers. r.in.arc Convert an ESRI ARC/INFO ascii raster file (GRID) into a (binary) raster map layer. r.in.ascii Convert an ASCII raster text file into a (binary) raster map layer. r.in.bin Import a binary raster file into a GRASS raster map layer. r.in.gdal Import GDAL supported raster file into a binary raster map layer. r.in.gridatb Imports GRIDATB.FOR map file (TOPMODEL) into GRASS raster map r.in.mat Import a binary MAT-File(v4) to a GRASS raster. r.in.poly Create raster maps from ascii polygon/line data files in the current directory. r.in.srtm Import SRTM HGT files into GRASS r.info Outputs basic information about a user-specified raster map layer. r.kappa Calculate error matrix and kappa parameter for accuracy assessment of classification result. r.le.patch r.le.pixel r.le.setup r.le.setup r.le.trace r.los Line-of-sight raster analysis program. r.mapcalc r.mapcalc r.mapcalculator r.mapcalculator - Calculates new raster map from r.mapcalc expression r.median Finds the median of values in a cover map within areas assigned the same category value in a user-specified base map. r.mfilter Raster file matrix filter. r.mode Finds the mode of values in a cover map within areas assigned the same category value in a user-specified base map. r.neighbors Makes each cell category value a function of the category values assigned to the cells around it, and stores new cell values in an output raster map layer. r.null The function of r.null is to explicitly create the NULL-value bitmap file. r.out.arc Converts a raster map layer into an ESRI ARCGRID file. r.out.ascii Converts a raster map layer into an ASCII text file. r.out.bin Exports a GRASS raster to a binary array. r.out.gdal Exports GRASS raster data into various formats (requires GDAL) r.out.gridatb Exports GRASS raster map to GRIDATB.FOR map file (TOPMODEL) r.out.mat Exports a GRASS raster to a binary MAT-File. r.out.mpeg Raster File Series to MPEG Conversion Program. r.out.png Export GRASS raster as non-georeferenced PNG image format. r.out.pov Converts a raster map layer into a height-field file for POVRAY. r.out.ppm Converts a GRASS raster file to a PPM image file at the pixel resolution of the CURRENTLY DEFINED REGION. r.out.ppm3 Converts 3 GRASS raster layers (R,G,B) to a PPM image file at the pixel resolution of the CURRENTLY DEFINED REGION. r.out.tiff Exports a GRASS raster file to a 8/24bit TIFF image file at the pixel resolution of the currently defined region. r.param.scale Extracts terrain parameters from a DEM. Uses a multi-scalar approach by taking fitting quadratic parameters to any size window (via least squares) r.patch Creates a composite raster map layer by using known category values from one (or more) map layer(s) to fill in areas of "no data" in another map layer. r.plane Creates raster plane map given dip (inclination), aspect (azimuth), and one point r.profile Outputs the raster map layer values lying on user-defined line(s). r.proj Re-project a raster map from one location to the current location. r.quant This routine produces the quantization file for a floating-point map. r.random.cells Generates random cell values with spatial dependence. r.random Creates a raster map layer and vector point map containing randomly located sites. r.random.surface Generates random surface(s) with spatial dependence. r.reclass.area Reclasses a raster map greater or less than user specified area size (in hectares) r.reclass Creates a new map layer whose category values are based upon the user's reclassification of categories in an existing raster map layer. r.recode Recode raster maps. r.region Sets the boundary definitions for a raster map. r.regression.line Calculates linear regression from two raster maps: y = a + b*x r.report Reports statistics for raster map layers. r.resamp.rst Reinterpolates and computes topographic analysis from input raster file to a new raster file (possibly with different resolution) using regularized spline with tension and smoothing. r.resample GRASS raster map layer data resampling capability. r.rescale.eq Rescales histogram equalized the range of categoryvalues in a raster map layer. r.rescale Rescales the range of category values in a raster map layer. r.ros Generates three, or four raster map layers showing 1) the base (perpendicular) rate of spread (ROS), 2) the maximum (forward) ROS, 3) the direction of the maximum ROS, and optionally 4) the maximum potential spotting distance. r.series Makes each output cell value a function of the values assigned to the corresponding cells in the input raster map layers. r.shaded.relief Creates shaded relief map from an elevation map (DEM). r.slope.aspect Generates raster map layers of slope, aspect, curvatures and partial derivatives from a raster map layer of true elevation values. Aspect is calculated counterclockwise from east. r.spread Simulates elliptically anisotropic spread on a graphics window and generates a raster map of the cumulative time of spread, given raster maps containing the rates of spread (ROS), the ROS directions and the spread origins. It optionally produces raster maps to contain backlink UTM coordinates for tracing spread paths. r.spreadpath Recursively traces the least cost path backwards to cells from which the cumulative cost was determined. r.statistics Category or object oriented statistics. r.stats Generates area statistics for raster map layers. r.sum Sums up the raster cell values. r.sun Computes direct (beam), diffuse and reflected solar irradiation raster maps for given day, latitude, surface and atmospheric conditions. Solar parameters (e.g. sunrise, sunset times, declination, extraterrestrial irradiance, daylight length) are saved in a local text file. Alternatively, a local time can be specified to compute solar incidence angle and/or irradiance raster maps. The shadowing effect of the topography is optionally incorporated. r.sunmask Calculates cast shadow areas from sun position and DEM. Either A: exact sun position is specified, or B: date/time to calculate the sun position by r.sunmask itself. r.surf.area Surface area estimation for rasters. r.surf.contour Surface generation program from rasterized contours. r.surf.fractal GRASS module to create a fractal surface of a given fractal dimension. Uses spectral synthesis method. Can create intermediate layers showing the build up of different spectral coefficients (see Saupe, pp.106-107 for an example of this). Use this module to generate naturally looking synthetical elevation models (DEM). r.surf.gauss GRASS module to produce a raster map layer of gaussian deviates whose mean and standard deviation can be expressed by the user. It uses a gaussian random number generator. r.surf.idw Surface interpolation utility for raster map layers. r.surf.idw2 Surface generation program. r.surf.random Produces a raster map layer of uniform random deviates whose range can be expressed by the user. r.terraflow Flow computation for massive grids (Float version). r.texture Generate images with textural features from a raster map r.thin Thins non-zero cells that denote linear features in a raster map layer. r.timestamp Print/add/remove a timestamp for a raster map. r.to.vect Converts a raster map into a vector map layer. r.topidx Creates topographic index, ln(a/tan(beta)), map from elevation map. r.topmodel Simulates TOPMODEL which is a physically based hydrologic model. r.transect Outputs raster map layer values lying along user defined transect line(s). r.univar Calculates univariate statistics from the non-null cells of a raster map. r.univar.sh calculates univariate statistics from a GRASS raster map r.water.outlet Watershed basin creation program. r.watershed Watershed basin analysis program. r.what Queries raster map layers on their category values and category labels.

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