QGIS algorithm - r.cost

QGIS Algorithm provided by GRASS r.cost (grass:r.cost). Creates a raster layer of cumulative cost of moving across a raster layer whose cell values represent cost.

grass_r_cost(
  input = qgisprocess:::qgis_default_value(),
  start_coordinates = qgisprocess:::qgis_default_value(),
  stop_coordinates = qgisprocess:::qgis_default_value(),
  .k = qgisprocess:::qgis_default_value(),
  .n = qgisprocess:::qgis_default_value(),
  start_points = qgisprocess:::qgis_default_value(),
  stop_points = qgisprocess:::qgis_default_value(),
  start_raster = qgisprocess:::qgis_default_value(),
  max_cost = qgisprocess:::qgis_default_value(),
  null_cost = qgisprocess:::qgis_default_value(),
  memory = qgisprocess:::qgis_default_value(),
  output = qgisprocess:::qgis_default_value(),
  nearest = qgisprocess:::qgis_default_value(),
  outdir = 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_SNAP_TOLERANCE_PARAMETER = qgisprocess:::qgis_default_value(),
  GRASS_MIN_AREA_PARAMETER = qgisprocess:::qgis_default_value(),
  ...,
  .complete_output = .complete_output_option(),
  .quiet = .quiet_option(),
  .messages = .message_option()
)

Arguments

input

raster - Unit cost layer. Path to a raster layer.

start_coordinates

point - Coordinates of starting point(s) (E,N). Point coordinate as an 'x,y' string, e.g. '1.5,10.1'.

stop_coordinates

point - Coordinates of stopping point(s) (E,N). Point coordinate as an 'x,y' string, e.g. '1.5,10.1'.

.k

boolean - Use the 'Knight's move'; slower, but more accurate. 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: -k.

.n

boolean - Keep null values in output raster layer. 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: -n.

start_points

source - Start points. Path to a vector layer.

stop_points

source - Stop points. Path to a vector layer.

start_raster

raster - Name of starting raster points map. Path to a raster layer.

max_cost

number - Maximum cumulative cost. 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.

null_cost

number - Cost assigned to null cells. By default, null cells are excluded. 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.

memory

number - Maximum memory to be used in MB. 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.

output

rasterDestination - Cumulative cost. Path for new raster layer.

nearest

rasterDestination - Cost allocation map. Path for new raster layer.

outdir

rasterDestination - Movement directions. 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_SNAP_TOLERANCE_PARAMETER

number - v.in.ogr snap tolerance (-1 = no snap). 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_MIN_AREA_PARAMETER

number - v.in.ogr min area. 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.

...

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

• nearest - outputRaster - Cost allocation map

• outdir - outputRaster - Movement directions

• output - outputRaster - Cumulative cost