QGIS algorithm - r.flow

QGIS Algorithm provided by GRASS r.flow (grass:r.flow). Construction of flowlines, flowpath lengths, and flowaccumulation (contributing areas) from a raster digital elevation model (DEM).

grass_r_flow(
  elevation = qgisprocess:::qgis_default_value(),
  aspect = qgisprocess:::qgis_default_value(),
  barrier = qgisprocess:::qgis_default_value(),
  skip = qgisprocess:::qgis_default_value(),
  bound = qgisprocess:::qgis_default_value(),
  .u = qgisprocess:::qgis_default_value(),
  .arg_3 = qgisprocess:::qgis_default_value(),
  .m = qgisprocess:::qgis_default_value(),
  flowline = qgisprocess:::qgis_default_value(),
  flowlength = qgisprocess:::qgis_default_value(),
  flowaccumulation = qgisprocess:::qgis_default_value(),
  GRASS_REGION_PARAMETER = qgisprocess:::qgis_default_value(),
  GRASS_REGION_CELLSIZE_PARAMETER = qgisprocess:::qgis_default_value(),
  GRASS_RASTER_FORMAT_OPT = qgisprocess:::qgis_default_value(),
  GRASS_RASTER_FORMAT_META = qgisprocess:::qgis_default_value(),
  GRASS_OUTPUT_TYPE_PARAMETER = qgisprocess:::qgis_default_value(),
  GRASS_VECTOR_DSCO = qgisprocess:::qgis_default_value(),
  GRASS_VECTOR_LCO = qgisprocess:::qgis_default_value(),
  GRASS_VECTOR_EXPORT_NOCAT = qgisprocess:::qgis_default_value(),
  ...,
  .complete_output = .complete_output_option(),
  .quiet = .quiet_option(),
  .messages = .message_option()
)

Arguments

elevation

raster - Elevation. Path to a raster layer.

aspect

raster - Aspect. Path to a raster layer.

barrier

raster - Barrier. Path to a raster layer.

skip

number - Number of cells between flowlines. A numeric value. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression.

bound

number - Maximum number of segments per flowline. A numeric value. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression.

.u

boolean - Compute upslope flowlines instead of default downhill flowlines. 1 for true/yes. 0 for false/no. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression. Original algorithm parameter name: -u.

.arg_3

boolean - 3-D lengths instead of 2-D. 1 for true/yes. 0 for false/no. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression. Original algorithm parameter name: -3.

.m

boolean - Use less memory, at a performance penalty. 1 for true/yes. 0 for false/no. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression. Original algorithm parameter name: -m.

flowline

vectorDestination - Flow line. Path for new vector layer.

flowlength

rasterDestination - Flow path length. Path for new raster layer.

flowaccumulation

rasterDestination - Flow accumulation. Path for new raster layer.

GRASS_REGION_PARAMETER

extent - GRASS GIS region extent. A comma delimited string of x min, x max, y min, y max. E.g. '4,10,101,105'. Path to a layer. The extent of the layer is used..

GRASS_REGION_CELLSIZE_PARAMETER

number - GRASS GIS region cellsize (leave 0 for default). A numeric value. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression.

GRASS_RASTER_FORMAT_OPT

string - Output Rasters format options (createopt). String value. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression.

GRASS_RASTER_FORMAT_META

string - Output Rasters format metadata options (metaopt). String value. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression.

GRASS_OUTPUT_TYPE_PARAMETER

enum of ("auto", "point", "line", "area") - v.out.ogr output type. Number of selected option, e.g. '1'. Comma separated list of options, e.g. '1,3'.

GRASS_VECTOR_DSCO

string - v.out.ogr output data source options (dsco). String value. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression.

GRASS_VECTOR_LCO

string - v.out.ogr output layer options (lco). String value. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression.

GRASS_VECTOR_EXPORT_NOCAT

boolean - Also export features without category (not labeled). Otherwise only features with category are exported. 1 for true/yes. 0 for false/no. field:FIELD_NAME to use a data defined value taken from the FIELD_NAME field. expression:SOME EXPRESSION to use a data defined value calculated using a custom QGIS expression.

...

further parameters passed to qgisprocess::qgis_run_algorithm()

.complete_output

logical specifying if complete out of qgisprocess::qgis_run_algorithm() should be used (TRUE) or first output (most likely the main) should read (FALSE). Default value is TRUE.

.quiet

logical specifying if parameter .quiet for qgisprocess::qgis_run_algorithm() Default value is TRUE.

.messages

logical specifying if messages from qgisprocess::qgis_run_algorithm() should be printed (TRUE) or not (FALSE). Default value is FALSE.

Details

Outputs description

• flowaccumulation - outputRaster - Flow accumulation

• flowlength - outputRaster - Flow path length

• flowline - outputVector - Flow line