r.flow Construction of slope curves (flowlines), flowpath lengths, and flowline densities (upslope areas) from a raster digital elevation model (DEM). Raster (r.*) ParameterRaster|elevin|Elevation|False ParameterRaster|aspin|Aspect|False ParameterRaster|barin|Barriers|False ParameterNumber|skip|Number of cells between flowlines|None|None|1.0 ParameterNumber|bound|Maximum number of segments per flowline|None|None|5.0 ParameterBoolean|-u|Compute upslope flowlines instead of default downhill flowlines|False ParameterBoolean|-3|3-D lengths instead of 2-D|False *ParameterBoolean|-m|Use less memory, at a performance penalty|False OutputRaster|flout|Flowline OutputRaster|lgout|Flowpath length OutputRaster|dsout|Flowline density