R/grass_v_class.R

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

##' QGIS Algorithm provided by GRASS v.class (grass:v.class). Classifies attribute data, e.g. for thematic mapping.
##'
##' @title QGIS algorithm - v.class
##'
##' @param map `source` - Input vector layer. Path to a vector layer.
##' @param column `field` - Column name or expression. The name of an existing field. ; delimited list of existing field names.
##' @param where `string` - WHERE conditions of SQL statement without 'where' keyword. 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.
##' @param algorithm `enum`  of `("int", "std", "qua", "equ")` - Algorithm to use for classification. Number of selected option, e.g. '1'. Comma separated list of options, e.g. '1,3'.
##' @param nbclasses `number` - Number of classes to define. 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.
##' @param .g `boolean` - Print only class breaks (without min and max). 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: -g.
##' @param html `fileDestination` - Classification. Path for new file.
##' @param 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..
##' @param 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.
##' @param 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.
##' @param ... further parameters passed to `qgisprocess::qgis_run_algorithm()`
##' @param .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`.
##' @param .quiet logical specifying if parameter `.quiet` for `qgisprocess::qgis_run_algorithm()` Default value is `TRUE`.
##' @param .messages logical specifying if messages from `qgisprocess::qgis_run_algorithm()` should be printed (`TRUE`) or not (`FALSE`). Default value is `FALSE`.
##'
##' @details
##' ## Outputs description
##' * html - outputHtml - Classification
##'
##'
##' @export
##' @md
##' @importFrom qgisprocess qgis_run_algorithm

grass_v_class <- function(map = qgisprocess:::qgis_default_value(), column = qgisprocess:::qgis_default_value(), where = qgisprocess:::qgis_default_value(), algorithm = qgisprocess:::qgis_default_value(), nbclasses = qgisprocess:::qgis_default_value(), .g = qgisprocess:::qgis_default_value(), html = qgisprocess:::qgis_default_value(), GRASS_REGION_PARAMETER = 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()) {

  check_algorithm_necessities("grass:v.class")

  if (.messages){
    output <- qgisprocess::qgis_run_algorithm("grass:v.class", `map` = map, `column` = column, `where` = where, `algorithm` = algorithm, `nbclasses` = nbclasses, `-g` = .g, `html` = html, `GRASS_REGION_PARAMETER` = GRASS_REGION_PARAMETER, `GRASS_SNAP_TOLERANCE_PARAMETER` = GRASS_SNAP_TOLERANCE_PARAMETER, `GRASS_MIN_AREA_PARAMETER` = GRASS_MIN_AREA_PARAMETER,..., .quiet = .quiet)
  } else {
    suppressMessages(
      output <- qgisprocess::qgis_run_algorithm("grass:v.class", `map` = map, `column` = column, `where` = where, `algorithm` = algorithm, `nbclasses` = nbclasses, `-g` = .g, `html` = html, `GRASS_REGION_PARAMETER` = GRASS_REGION_PARAMETER, `GRASS_SNAP_TOLERANCE_PARAMETER` = GRASS_SNAP_TOLERANCE_PARAMETER, `GRASS_MIN_AREA_PARAMETER` = GRASS_MIN_AREA_PARAMETER,..., .quiet = .quiet)
      )
  }

  if (.complete_output) {
    return(output)
  }
  else{
    qgisprocess::qgis_extract_output(output, "html")
  }
}