grass_r_walk_points: QGIS algorithm - r.walk.points

In JanCaha/r_package_qgis: An extension of package "qgisprocess" providing direct R functions for QGIS functions

QGIS algorithm - r.walk.points

Description

QGIS Algorithm provided by GRASS r.walk.points (grass:r.walk.points). r.walk.points - Creates a raster map showing the anisotropic cumulative cost of moving between different geographic locations on an input raster map whose cell category values represent cost from point vector layers.

Usage

grass_r_walk_points(
  elevation = qgisprocess:::qgis_default_value(),
  friction = qgisprocess:::qgis_default_value(),
  start_points = qgisprocess:::qgis_default_value(),
  stop_points = qgisprocess:::qgis_default_value(),
  walk_coeff = qgisprocess:::qgis_default_value(),
  lambda = qgisprocess:::qgis_default_value(),
  slope_factor = qgisprocess:::qgis_default_value(),
  max_cost = qgisprocess:::qgis_default_value(),
  null_cost = qgisprocess:::qgis_default_value(),
  memory = qgisprocess:::qgis_default_value(),
  .k = qgisprocess:::qgis_default_value(),
  .n = qgisprocess:::qgis_default_value(),
  output = 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

elevation	raster - Name of input elevation raster map. Path to a raster layer.
friction	raster - Name of input raster map containing friction costs. Path to a raster layer.
start_points	source - Start points. Path to a vector layer.
stop_points	source - Stop points. Path to a vector layer.
walk_coeff	string - Coefficients for walking energy formula parameters a,b,c,d. 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.
lambda	number - Lambda coefficients for combining walking energy and friction 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.
slope_factor	number - Slope factor determines travel energy cost per height step. 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.
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.
.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.
output	rasterDestination - Cumulative cost. 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

• outdir - outputRaster - Movement Directions

• output - outputRaster - Cumulative cost

JanCaha/r_package_qgis documentation built on Nov. 3, 2024, 5:25 p.m.