R/qgis_extractbyexpression.R
qgis_extractbyexpression.RdQGIS Algorithm provided by QGIS (native c++) Extract by expression (native:extractbyexpression). Creates a vector layer that only contains features matching a QGIS expression from an input layer. 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.
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()
)source - Input layer. Path to a vector layer.
expression - Expression. A valid QGIS expression string, e.g "road_name" = 'MAIN RD'.
sink - Matching features. Path for new vector layer.
sink - Non-matching. Path for new vector layer.
further parameters passed to qgisprocess::qgis_run_algorithm()
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.
logical specifying if parameter .quiet for qgisprocess::qgis_run_algorithm() Default value is TRUE.
logical specifying if messages from qgisprocess::qgis_run_algorithm() should be printed (TRUE) or not (FALSE). Default value is FALSE.