qgis_geometrybyexpression: QGIS algorithm - Geometry by expression

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

QGIS algorithm - Geometry by expression

Description

QGIS Algorithm provided by QGIS (native c++) Geometry by expression (native:geometrybyexpression). This algorithm updates existing geometries (or creates new geometries) for input features by use of a QGIS expression. This allows complex geometry modifications which can utilize all the flexibility of the QGIS expression engine to manipulate and create geometries for output features. For help with QGIS expression functions, see the inbuilt help for specific functions which is available in the expression builder.

Usage

qgis_geometrybyexpression(
  INPUT = qgisprocess:::qgis_default_value(),
  OUTPUT_GEOMETRY = qgisprocess:::qgis_default_value(),
  WITH_Z = qgisprocess:::qgis_default_value(),
  WITH_M = qgisprocess:::qgis_default_value(),
  EXPRESSION = qgisprocess:::qgis_default_value(),
  OUTPUT = qgisprocess:::qgis_default_value(),
  ...,
  .complete_output = .complete_output_option(),
  .quiet = .quiet_option(),
  .messages = .message_option()
)

Arguments

INPUT	source - Input layer. Path to a vector layer.
OUTPUT_GEOMETRY	enum of ⁠("Polygon", "Line", "Point")⁠ - Output geometry type. Number of selected option, e.g. '1'. Comma separated list of options, e.g. '1,3'.
WITH_Z	boolean - Output geometry has z dimension. 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.
WITH_M	boolean - Output geometry has m values. 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.
EXPRESSION	expression - Geometry expression. A valid QGIS expression string, e.g "road_name" = 'MAIN RD'.
OUTPUT	sink - Modified geometry. Path for new vector layer.
...	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

• OUTPUT - outputVector - Modified geometry

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