qgis_extractbyexpression: QGIS algorithm - Extract by expression

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

QGIS algorithm - Extract by expression

Description

QGIS Algorithm provided by QGIS (native c++) Extract by expression (native:extractbyexpression). This algorithm creates a new vector layer that only contains matching features from an input layer. The criteria for adding features to the resulting layer is based on a QGIS expression. For help with QGIS expression functions, see the inbuilt help for specific functions which is available in the expression builder.

Usage

qgis_extractbyexpression(
  INPUT = qgisprocess:::qgis_default_value(),
  EXPRESSION = qgisprocess:::qgis_default_value(),
  OUTPUT = qgisprocess:::qgis_default_value(),
  FAIL_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.
EXPRESSION	expression - Expression. A valid QGIS expression string, e.g "road_name" = 'MAIN RD'.
OUTPUT	sink - Matching features. Path for new vector layer.
FAIL_OUTPUT	sink - Non-matching. 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

• FAIL_OUTPUT - outputVector - Non-matching

• OUTPUT - outputVector - Matching features

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