QGIS algorithm - Add unique value index field

Source: R/qgis_adduniquevalueindexfield.R

QGIS Algorithm provided by QGIS (native c++) Add unique value index field (native:adduniquevalueindexfield). This algorithm takes a vector layer and an attribute and adds a new numeric field. Values in this field correspond to values in the specified attribute, so features with the same value for the attribute will have the same value in the new numeric field. This creates a numeric equivalent of the specified attribute, which defines the same classes. The new attribute is not added to the input layer but a new layer is generated instead. Optionally, a separate table can be output which contains a summary of the class field values mapped to the new unique numeric value.

qgis_adduniquevalueindexfield(
  INPUT = qgisprocess:::qgis_default_value(),
  FIELD = qgisprocess:::qgis_default_value(),
  FIELD_NAME = qgisprocess:::qgis_default_value(),
  OUTPUT = qgisprocess:::qgis_default_value(),
  SUMMARY_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.

FIELD

field - Class field. The name of an existing field. ; delimited list of existing field names.

FIELD_NAME

string - Output field name. 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.

OUTPUT

sink - Layer with index field. Path for new vector layer.

SUMMARY_OUTPUT

sink - Class summary. 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 - Layer with index field

  • SUMMARY_OUTPUT - outputVector - Class summary