QGIS/python/plugins/processing/algs/EquivalentNumField.py
2013-08-20 09:22:03 +02:00

81 lines
3.3 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 processing.core.GeoAlgorithm import GeoAlgorithm
from PyQt4.QtCore import *
from qgis.core import *
from processing.parameters.ParameterVector import ParameterVector
from processing.core.QGisLayers import QGisLayers
from processing.outputs.OutputVector import OutputVector
from processing.parameters.ParameterTableField import ParameterTableField
class EquivalentNumField(GeoAlgorithm):
INPUT = "INPUT"
OUTPUT = "OUTPUT"
FIELD = "FIELD"
#===========================================================================
# def getIcon(self):
# return QtGui.QIcon(os.path.dirname(__file__) + "/../images/qgis.png")
#===========================================================================
def processAlgorithm(self, progress):
fieldname = self.getParameterValue(self.FIELD)
output = self.getOutputFromName(self.OUTPUT)
vlayer = QGisLayers.getObjectFromUri(self.getParameterValue(self.INPUT))
vprovider = vlayer.dataProvider()
fieldindex = vlayer.fieldNameIndex(fieldname)
fields = vprovider.fields()
fields.append(QgsField("NUM_FIELD", QVariant.Int))
writer = output.getVectorWriter(fields, vprovider.geometryType(), vlayer.crs() )
outFeat = QgsFeature()
inGeom = QgsGeometry()
nElement = 0
classes = {}
features = QGisLayers.features(vlayer)
nFeat = len(features)
for feature in features:
progress.setPercentage(int((100 * nElement)/nFeat))
nElement += 1
inGeom = feature.geometry()
outFeat.setGeometry( inGeom )
atMap = feature.attributes()
clazz = atMap[fieldindex]
if clazz not in classes:
classes[clazz] = len(classes.keys())
atMap.append(classes[clazz])
outFeat.setAttributes(atMap)
writer.addFeature( outFeat )
del writer
def defineCharacteristics(self):
self.name = "Create equivalent numerical field"
self.group = "Vector table tools"
self.addParameter(ParameterVector(self.INPUT, "Input layer", [ParameterVector.VECTOR_TYPE_ANY]))
self.addParameter(ParameterTableField(self.FIELD, "Class field", self.INPUT))
self.addOutput(OutputVector(self.OUTPUT, "Output layer"))