mirror of
https://github.com/qgis/QGIS.git
synced 2025-10-31 00:06:02 -04:00
88 lines
3.5 KiB
Python
88 lines
3.5 KiB
Python
# -*- coding: utf-8 -*-
|
|
|
|
"""
|
|
***************************************************************************
|
|
RandomSelection.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__ = '$Format:%H$'
|
|
|
|
import random
|
|
|
|
from processing.core.GeoAlgorithm import GeoAlgorithm
|
|
from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException
|
|
from processing.core.parameters import ParameterSelection
|
|
from processing.core.parameters import ParameterVector
|
|
from processing.core.parameters import ParameterNumber
|
|
from processing.core.outputs import OutputVector
|
|
from processing.tools import dataobjects
|
|
|
|
|
|
class RandomSelection(GeoAlgorithm):
|
|
|
|
INPUT = 'INPUT'
|
|
OUTPUT = 'OUTPUT'
|
|
METHOD = 'METHOD'
|
|
NUMBER = 'NUMBER'
|
|
|
|
def defineCharacteristics(self):
|
|
self.allowOnlyOpenedLayers = True
|
|
self.name, self.i18n_name = self.trAlgorithm('Random selection')
|
|
self.group, self.i18n_group = self.trAlgorithm('Vector selection tools')
|
|
|
|
self.methods = [self.tr('Number of selected features'),
|
|
self.tr('Percentage of selected features')]
|
|
|
|
self.addParameter(ParameterVector(self.INPUT,
|
|
self.tr('Input layer'), [ParameterVector.VECTOR_TYPE_ANY]))
|
|
self.addParameter(ParameterSelection(self.METHOD,
|
|
self.tr('Method'), self.methods, 0))
|
|
self.addParameter(ParameterNumber(self.NUMBER,
|
|
self.tr('Number/percentage of selected features'), 0, None, 10))
|
|
self.addOutput(OutputVector(self.OUTPUT, self.tr('Selection'), True))
|
|
|
|
def processAlgorithm(self, progress):
|
|
filename = self.getParameterValue(self.INPUT)
|
|
layer = dataobjects.getObjectFromUri(filename)
|
|
method = self.getParameterValue(self.METHOD)
|
|
|
|
featureCount = layer.featureCount()
|
|
value = int(self.getParameterValue(self.NUMBER))
|
|
|
|
layer.removeSelection()
|
|
|
|
if method == 0:
|
|
if value > featureCount:
|
|
raise GeoAlgorithmExecutionException(
|
|
self.tr('Selected number is greater than feature count. '
|
|
'Choose a lower value and try again.'))
|
|
else:
|
|
if value > 100:
|
|
raise GeoAlgorithmExecutionException(
|
|
self.tr("Percentage can't be greater than 100. Set a "
|
|
"different value and try again."))
|
|
value = int(round(value / 100.0000, 4) * featureCount)
|
|
|
|
selran = random.sample(xrange(0, featureCount), value)
|
|
|
|
layer.setSelectedFeatures(selran)
|
|
self.setOutputValue(self.OUTPUT, filename)
|