QGIS/python/plugins/processing/algs/qgis/EquivalentNumField.py
2017-08-22 23:36:42 +10:00

96 lines
3.5 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
EquivalentNumField.py
---------------------
Date : August 2012
Copyright : (C) 2012 by Victor Olaya
Email : volayaf at gmail dot com
***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
***************************************************************************
"""
__author__ = 'Victor Olaya'
__date__ = 'August 2012'
__copyright__ = '(C) 2012, Victor Olaya'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'
from qgis.PyQt.QtCore import QVariant
from qgis.core import (QgsField,
QgsFeatureSink,
QgsProcessingParameterFeatureSource,
QgsProcessingParameterField,
QgsProcessingParameterFeatureSink)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
class EquivalentNumField(QgisAlgorithm):
INPUT = 'INPUT'
OUTPUT = 'OUTPUT'
FIELD = 'FIELD'
def group(self):
return self.tr('Vector table')
def __init__(self):
super().__init__()
def initAlgorithm(self, config=None):
self.addParameter(QgsProcessingParameterFeatureSource(self.INPUT,
self.tr('Input layer')))
self.addParameter(QgsProcessingParameterField(self.FIELD,
self.tr('Class field'),
None, self.INPUT, QgsProcessingParameterField.Any))
self.addParameter(QgsProcessingParameterFeatureSink(self.OUTPUT, self.tr('Layer with index field')))
def name(self):
return 'adduniquevalueindexfield'
def displayName(self):
return self.tr('Add unique value index field')
def processAlgorithm(self, parameters, context, feedback):
source = self.parameterAsSource(parameters, self.INPUT, context)
fields = source.fields()
fields.append(QgsField('NUM_FIELD', QVariant.Int))
(sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
fields, source.wkbType(), source.sourceCrs())
field_name = self.parameterAsString(parameters, self.FIELD, context)
field_index = source.fields().lookupField(field_name)
classes = {}
features = source.getFeatures()
total = 100.0 / source.featureCount() if source.featureCount() else 0
for current, feature in enumerate(features):
if feedback.isCanceled():
break
feedback.setProgress(int(current * total))
attributes = feature.attributes()
clazz = attributes[field_index]
if clazz not in classes:
classes[clazz] = len(list(classes.keys()))
attributes.append(classes[clazz])
feature.setAttributes(attributes)
sink.addFeature(feature, QgsFeatureSink.FastInsert)
return {self.OUTPUT: dest_id}