R/remove.R

In ropensci/lawn: Client for 'Turfjs' for 'Geospatial' Analysis

#' Remove things from a FeatureCollection
#'
#' Takes a [data-FeatureCollection] of any type, a property, and a
#' value and returns a [data-FeatureCollection] with features
#' matching that property-value pair removed.
#'
#' @export
#'
#' @param features A set of input features.
#' @param property Property to filter.
#' @param value Value to filter.
#' @template lint
#' @family data functions
#' @return A [data-FeatureCollection].
#' @examples
#' cat(lawn_data$remove_features)
#' lawn_remove(lawn_data$remove_features, 'marker-color', '#00f')
#' lawn_remove(lawn_data$remove_features, 'marker-color', '#0f0')
lawn_remove <- function(features, property, value, lint = FALSE) {
  features <- convert(features)
  lawnlint(features, lint)
  ct$eval('
    fun = function(cc, k, v) {
      var nfc = turf.featureCollection([]);
      for (var i = 0; i < cc.features.length; i++) {
          if(cc.features[i].properties[k] === v) {
          nfc.features.push(cc.features[i]);
        }
      }
      return nfc;
    }
  ')
  ct$eval(sprintf("var rmv = fun(%s, '%s', '%s');", features, property, value))
  as.fc(ct$get("rmv"))
}