QGIS/python/plugins/processing/algs/qgis/PointsInPolygonWeighted.py
Nyall Dawson f84d703234 Add method QgsProcessingUtils::mapLayerFromString
Algorithms and other processing code should use this method
(instead of dataobjects.getLayerFromString) to
retrieve layers from a string, as it considers the processing
context and allows resolving strings to temporarily stored layers.

This permits processing models to function correctly when
intermediate results are stored as memory layers. Subsequent
model algorithms can then access these temporary layers as inputs.
All temporary layers will be removed when the context object
is destroyed after the model algorithm is run.
2017-05-02 12:33:04 +10:00

142 lines
5.7 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
PointsInPolygon.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. *
* *
***************************************************************************
"""
from builtins import str
__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 (QgsApplication,
QgsField,
QgsFeatureRequest,
QgsFeature,
QgsGeometry,
QgsProcessingUtils)
from processing.core.GeoAlgorithm import GeoAlgorithm
from processing.core.parameters import ParameterVector
from processing.core.parameters import ParameterString
from processing.core.parameters import ParameterTableField
from processing.core.outputs import OutputVector
from processing.tools import dataobjects, vector
class PointsInPolygonWeighted(GeoAlgorithm):
POLYGONS = 'POLYGONS'
POINTS = 'POINTS'
OUTPUT = 'OUTPUT'
FIELD = 'FIELD'
WEIGHT = 'WEIGHT'
# =========================================================================
# def getIcon(self):
# return QIcon(os.path.dirname(__file__) + "/icons/sum_points.png")
# =========================================================================
def icon(self):
return QgsApplication.getThemeIcon("/providerQgis.svg")
def svgIconPath(self):
return QgsApplication.iconPath("providerQgis.svg")
def group(self):
return self.tr('Vector analysis tools')
def name(self):
return 'countpointsinpolygonweighted'
def displayName(self):
return self.tr('Count points in polygon(weighted)')
def defineCharacteristics(self):
self.addParameter(ParameterVector(self.POLYGONS,
self.tr('Polygons'), [dataobjects.TYPE_VECTOR_POLYGON]))
self.addParameter(ParameterVector(self.POINTS,
self.tr('Points'), [dataobjects.TYPE_VECTOR_POINT]))
self.addParameter(ParameterTableField(self.WEIGHT,
self.tr('Weight field'), self.POINTS))
self.addParameter(ParameterString(self.FIELD,
self.tr('Count field name'), 'NUMPOINTS'))
self.addOutput(OutputVector(self.OUTPUT, self.tr('Weighted count'), datatype=[dataobjects.TYPE_VECTOR_POLYGON]))
def processAlgorithm(self, context, feedback):
polyLayer = dataobjects.QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.POLYGONS), context)
pointLayer = dataobjects.QgsProcessingUtils.mapLayerFromString(self.getParameterValue(self.POINTS), context)
fieldName = self.getParameterValue(self.FIELD)
fieldIdx = pointLayer.fields().lookupField(self.getParameterValue(self.WEIGHT))
fields = polyLayer.fields()
fields.append(QgsField(fieldName, QVariant.Int))
(idxCount, fieldList) = vector.findOrCreateField(polyLayer,
polyLayer.fields(), fieldName)
writer = self.getOutputFromName(self.OUTPUT).getVectorWriter(fields.toList(), polyLayer.wkbType(),
polyLayer.crs(), context)
spatialIndex = vector.spatialindex(pointLayer)
ftPoint = QgsFeature()
outFeat = QgsFeature()
geom = QgsGeometry()
features = QgsProcessingUtils.getFeatures(polyLayer, context)
total = 100.0 / QgsProcessingUtils.featureCount(polyLayer, context)
for current, ftPoly in enumerate(features):
geom = ftPoly.geometry()
engine = QgsGeometry.createGeometryEngine(geom.geometry())
engine.prepareGeometry()
attrs = ftPoly.attributes()
count = 0
points = spatialIndex.intersects(geom.boundingBox())
if len(points) > 0:
feedback.setProgressText(str(len(points)))
request = QgsFeatureRequest().setFilterFids(points).setSubsetOfAttributes([fieldIdx])
fit = pointLayer.getFeatures(request)
ftPoint = QgsFeature()
while fit.nextFeature(ftPoint):
tmpGeom = QgsGeometry(ftPoint.geometry())
if engine.contains(tmpGeom.geometry()):
weight = str(ftPoint.attributes()[fieldIdx])
try:
count += float(weight)
except:
# Ignore fields with non-numeric values
pass
outFeat.setGeometry(geom)
if idxCount == len(attrs):
attrs.append(count)
else:
attrs[idxCount] = count
outFeat.setAttributes(attrs)
writer.addFeature(outFeat)
feedback.setProgress(int(current * total))
del writer