[processing] add Vector split algorithm (addresses #5953)

alexbruy · alexbruy · commit e8d3d5a21425 · 2014-11-01T13:57:33.000+02:00
diff --git a/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py b/python/plugins/processing/algs/qgis/QGISAlgorithmProvider.py
@@ -33,6 +33,7 @@
 from processing.core.AlgorithmProvider import AlgorithmProvider
 from ftools.RegularPoints import RegularPoints
 from ftools.SymetricalDifference import SymetricalDifference
+from ftools.VectorSplit import VectorSplit
 
 from RandomExtract import RandomExtract
 from RandomExtractWithinSubsets import RandomExtractWithinSubsets
@@ -148,7 +149,7 @@ def __init__(self):
                         SelectByLocation(), RandomExtract(),
                         RandomExtractWithinSubsets(), ExtractByLocation(),
                         SpatialJoin(), RegularPoints(), SymetricalDifference(),
-                        DeleteColumn(),
+                        VectorSplit(), DeleteColumn(),
                         DeleteDuplicateGeometries(), TextToFloat(),
                         ExtractByAttribute(), SelectByAttribute(), Grid(),
                         Gridify(), HubDistance(), HubLines(), Merge(),
diff --git a/python/plugins/processing/algs/qgis/ftools/VectorSplit.py b/python/plugins/processing/algs/qgis/ftools/VectorSplit.py
@@ -0,0 +1,86 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    VectorSplit.py
+    ---------------------
+    Date                 : September 2014
+    Copyright            : (C) 2014 by Alexander Bruy
+    Email                : alexander dot bruy 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__ = 'Alexander Bruy'
+__date__ = 'September 2014'
+__copyright__ = '(C) 2014, Alexander Bruy'
+
+# This will get replaced with a git SHA1 when you do a git archive
+
+__revision__ = '$Format:%H$'
+
+from PyQt4.QtCore import *
+from qgis.core import *
+from processing.core.GeoAlgorithm import GeoAlgorithm
+from processing.core.parameters import ParameterVector
+from processing.core.parameters import ParameterTableField
+from processing.core.outputs import OutputDirectory
+from processing.tools import dataobjects, vector
+
+
+class VectorSplit(GeoAlgorithm):
+
+    INPUT = 'INPUT'
+    FIELD = 'FIELD'
+    OUTPUT = 'OUTPUT'
+
+    def defineCharacteristics(self):
+        self.name = 'Split vector layer'
+        self.group = 'Vector general tools'
+        self.addParameter(ParameterVector(self.INPUT,
+            'Input layer', [ParameterVector.VECTOR_TYPE_ANY]))
+        self.addParameter(ParameterTableField(self.FIELD,
+            'Unique ID field', self.INPUT))
+
+        self.addOutput(OutputDirectory(self.OUTPUT, 'Output directory'))
+
+    def processAlgorithm(self, progress):
+        layer = dataobjects.getObjectFromUri(
+            self.getParameterValue(self.INPUT))
+        fieldName = self.getParameterValue(self.FIELD)
+
+        directory = self.getOutputValue(self.OUTPUT)
+
+        if directory.find('\\') != -1:
+            directory.replace('\\', '/')
+
+        if not directory.endswith("/"):
+            directory += '/'
+
+        fieldIndex = layer.fieldNameIndex(fieldName)
+        uniqueValues = vector.uniqueValues(layer, fieldIndex)
+        baseName = '{0}{1}_{2}'.format(directory, layer.name(), fieldName)
+
+        fields = layer.pendingFields()
+        crs = layer.dataProvider().crs()
+        geomType = layer.wkbType()
+
+        total = 100.0 / len(uniqueValues)
+        features = vector.features(layer)
+
+        for count, i in enumerate(uniqueValues):
+            fName = '{0}_{1}.shp'.format(baseName, unicode(i).strip())
+
+            writer = vector.VectorWriter(fName, None, fields, geomType, crs)
+            for f in features:
+                if f[fieldName] == i:
+                    writer.addFeature(f)
+            del writer
+
+            progress.setPercentage(int(count * total))
