QGIS/python/plugins/processing/algs/qgis/ZonalStatistics.py
Bas Couwenberg 2628c480c5 Don't include revision in sources.
Prevent changes to files that weren't changed between releases.
This eases review of the changes between releases significantly.
2019-05-17 16:47:47 +02:00

145 lines
6.7 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
ZonalStatistics.py
---------------------
Date : September 2016
Copyright : (C) 2016 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 2016'
__copyright__ = '(C) 2016, Alexander Bruy'
import os
from collections import OrderedDict
from qgis.PyQt.QtGui import QIcon
from qgis.analysis import QgsZonalStatistics
from qgis.core import (QgsProcessing,
QgsProcessingAlgorithm,
QgsProcessingParameterVectorLayer,
QgsProcessingParameterRasterLayer,
QgsProcessingParameterString,
QgsProcessingParameterBand,
QgsProcessingParameterEnum,
QgsProcessingOutputVectorLayer)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0]
class ZonalStatistics(QgisAlgorithm):
INPUT_RASTER = 'INPUT_RASTER'
RASTER_BAND = 'RASTER_BAND'
INPUT_VECTOR = 'INPUT_VECTOR'
COLUMN_PREFIX = 'COLUMN_PREFIX'
STATISTICS = 'STATS'
def icon(self):
return QIcon(os.path.join(pluginPath, 'images', 'zonalstats.png'))
def group(self):
return self.tr('Raster analysis')
def groupId(self):
return 'rasteranalysis'
def flags(self):
return super().flags() | QgsProcessingAlgorithm.FlagNoThreading
def __init__(self):
super().__init__()
self.bandNumber = None
self.columnPrefix = None
self.selectedStats = None
self.vectorLayer = None
self.raster_interface = None
self.raster_crs = None
self.raster_units_per_pixel_x = None
self.raster_units_per_pixel_y = None
def initAlgorithm(self, config=None):
self.STATS = OrderedDict([(self.tr('Count'), QgsZonalStatistics.Count),
(self.tr('Sum'), QgsZonalStatistics.Sum),
(self.tr('Mean'), QgsZonalStatistics.Mean),
(self.tr('Median'), QgsZonalStatistics.Median),
(self.tr('Std. dev.'), QgsZonalStatistics.StDev),
(self.tr('Min'), QgsZonalStatistics.Min),
(self.tr('Max'), QgsZonalStatistics.Max),
(self.tr('Range'), QgsZonalStatistics.Range),
(self.tr('Minority'), QgsZonalStatistics.Minority),
(self.tr('Majority (mode)'), QgsZonalStatistics.Majority),
(self.tr('Variety'), QgsZonalStatistics.Variety),
(self.tr('Variance'), QgsZonalStatistics.Variance),
(self.tr('All'), QgsZonalStatistics.All)])
self.addParameter(QgsProcessingParameterRasterLayer(self.INPUT_RASTER,
self.tr('Raster layer')))
self.addParameter(QgsProcessingParameterBand(self.RASTER_BAND,
self.tr('Raster band'),
1,
self.INPUT_RASTER))
self.addParameter(QgsProcessingParameterVectorLayer(self.INPUT_VECTOR,
self.tr('Vector layer containing zones'),
[QgsProcessing.TypeVectorPolygon]))
self.addParameter(QgsProcessingParameterString(self.COLUMN_PREFIX,
self.tr('Output column prefix'), '_'))
keys = list(self.STATS.keys())
self.addParameter(QgsProcessingParameterEnum(self.STATISTICS,
self.tr('Statistics to calculate'),
keys,
allowMultiple=True, defaultValue=[0, 1, 2]))
self.addOutput(QgsProcessingOutputVectorLayer(self.INPUT_VECTOR,
self.tr('Zonal statistics'),
QgsProcessing.TypeVectorPolygon))
def name(self):
return 'zonalstatistics'
def displayName(self):
return self.tr('Zonal statistics')
def prepareAlgorithm(self, parameters, context, feedback):
self.bandNumber = self.parameterAsInt(parameters, self.RASTER_BAND, context)
self.columnPrefix = self.parameterAsString(parameters, self.COLUMN_PREFIX, context)
st = self.parameterAsEnums(parameters, self.STATISTICS, context)
keys = list(self.STATS.keys())
self.selectedStats = 0
for i in st:
self.selectedStats |= self.STATS[keys[i]]
self.vectorLayer = self.parameterAsVectorLayer(parameters, self.INPUT_VECTOR, context)
rasterLayer = self.parameterAsRasterLayer(parameters, self.INPUT_RASTER, context)
self.raster_interface = rasterLayer.dataProvider().clone()
self.raster_crs = rasterLayer.crs()
self.raster_units_per_pixel_x = rasterLayer.rasterUnitsPerPixelX()
self.raster_units_per_pixel_y = rasterLayer.rasterUnitsPerPixelY()
return True
def processAlgorithm(self, parameters, context, feedback):
zs = QgsZonalStatistics(self.vectorLayer,
self.raster_interface,
self.raster_crs,
self.raster_units_per_pixel_x,
self.raster_units_per_pixel_y,
self.columnPrefix,
self.bandNumber,
QgsZonalStatistics.Statistics(self.selectedStats))
zs.calculateStatistics(feedback)
return {self.INPUT_VECTOR: self.vectorLayer}