# -*- coding: utf-8 -*-
#-----------------------------------------------------------
#
# fTools
# Copyright (C) 2008-2011 Carson Farmer
# EMAIL: carson.farmer (at) gmail.com
# WEB : http://www.ftools.ca/fTools.html
#
# A collection of data management and analysis tools for vector data
#
#-----------------------------------------------------------
#
# licensed under the terms of GNU GPL 2
#
# 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.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
#---------------------------------------------------------------------
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from qgis.core import *
from ui_frmPointDistance import Ui_Dialog
import csv, codecs, cStringIO
import ftools_utils
from math import *
class UnicodeWriter:
"""
A CSV writer which will write rows to CSV file "f",
which is encoded in the given encoding.
Taken from http://docs.python.org/library/csv.html
to allow handling of non-ascii output
"""
def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds):
# Redirect output to a queue
self.queue = cStringIO.StringIO()
self.writer = csv.writer(self.queue, dialect=dialect, **kwds)
self.stream = f
self.encoder = codecs.getincrementalencoder(encoding)()
def writerow(self, row):
try:
self.writer.writerow([s.encode("utf-8") for s in row])
except:
self.writer.writerow(row)
# Fetch UTF-8 output from the queue ...
data = self.queue.getvalue()
data = data.decode("utf-8")
# ... and re-encode it into the target encoding
data = self.encoder.encode(data)
# write to the target stream
self.stream.write(data)
# empty queue
self.queue.truncate(0)
def writerows(self, rows):
for row in rows:
self.writerow(row)
class Dialog(QDialog, Ui_Dialog):
def __init__(self, iface):
QDialog.__init__(self, iface.mainWindow())
self.iface = iface
# Set up the user interface from Designer.
self.setupUi(self)
QObject.connect(self.btnFile, SIGNAL("clicked()"), self.saveFile)
QObject.connect(self.inPoint1, SIGNAL("currentIndexChanged(QString)"), self.update1)
QObject.connect(self.inPoint2, SIGNAL("currentIndexChanged(QString)"), self.update2)
self.buttonOk = self.buttonBox_2.button( QDialogButtonBox.Ok )
# populate layer list
self.setWindowTitle(self.tr("Distance matrix"))
self.progressBar.setValue(0)
mapCanvas = self.iface.mapCanvas()
layers = ftools_utils.getLayerNames( [ QGis.Point ] )
self.inPoint1.addItems(layers)
self.inPoint2.addItems(layers)
def update1(self, inputLayer):
self.inField1.clear()
changedLayer = ftools_utils.getVectorLayerByName(unicode(inputLayer))
changedField = ftools_utils.getFieldList(changedLayer)
for i in changedField:
if changedField[i].type() == QVariant.Int or \
changedField[i].type() == QVariant.String:
self.inField1.addItem(unicode(changedField[i].name()))
def update2(self, inputLayer):
self.inField2.clear()
changedLayer = ftools_utils.getVectorLayerByName(unicode(inputLayer))
changedField = ftools_utils.getFieldList(changedLayer)
for i in changedField:
if changedField[i].type() == QVariant.Int or \
changedField[i].type() == QVariant.String:
self.inField2.addItem(unicode(changedField[i].name()))
def accept(self):
self.buttonOk.setEnabled( False )
if self.inPoint1.currentText() == "":
QMessageBox.information(self, self.tr("Create Point Distance Matrix"), self.tr("Please specify input point layer"))
elif self.outFile.text() == "":
QMessageBox.information(self, self.tr("Create Point Distance Matrix"), self.tr("Please specify output file"))
elif self.inPoint2.currentText() == "":
QMessageBox.information(self, self.tr("Create Point Distance Matrix"), self.tr("Please specify target point layer"))
elif self.inField1.currentText() == "":
QMessageBox.information(self, self.tr("Create Point Distance Matrix"), self.tr("Please specify input unique ID field"))
elif self.inField2.currentText() == "":
QMessageBox.information(self, self.tr("Create Point Distance Matrix"), self.tr("Please specify target unique ID field"))
else:
point1 = self.inPoint1.currentText()
point2 = self.inPoint2.currentText()
field1 = self.inField1.currentText()
field2 = self.inField2.currentText()
outPath = self.outFile.text()
if self.rdoLinear.isChecked(): matType = "Linear"
elif self.rdoStandard.isChecked(): matType = "Standard"
else: matType = "Summary"
if self.chkNearest.isChecked(): nearest = self.spnNearest.value()
else: nearest = 0
if outPath.contains("\\"):
outName = outPath.right((outPath.length() - outPath.lastIndexOf("\\")) - 1)
else:
outName = outPath.right((outPath.length() - outPath.lastIndexOf("/")) - 1)
if outName.endsWith(".csv"):
outName = outName.left(outName.length() - 4)
self.outFile.clear()
self.compute(point1, point2, field1, field2, outPath, matType, nearest, self.progressBar)
self.progressBar.setValue(100)
addToTOC = QMessageBox.information(self, "Create Point Distance Matrix", self.tr("Created output matrix:\n") + outPath)
self.progressBar.setValue(0)
self.buttonOk.setEnabled( True )
def saveFile(self):
self.outFile.clear()
fileDialog = QFileDialog()
outName = fileDialog.getSaveFileName(self, "Output Distance Matrix",".", "Delimited txt file (*.csv)")
fileCheck = QFile(outName)
filePath = QFileInfo(outName).absoluteFilePath()
if filePath.right(4) != ".csv": filePath = filePath + ".csv"
if not outName.isEmpty():
self.outFile.insert(filePath)
def compute(self, line1, line2, field1, field2, outPath, matType, nearest, progressBar):
layer1 = ftools_utils.getVectorLayerByName(line1)
layer2 = ftools_utils.getVectorLayerByName(line2)
provider1 = layer1.dataProvider()
provider2 = layer2.dataProvider()
allAttrs = provider1.attributeIndexes()
provider1.select(allAttrs)
allAttrs = provider2.attributeIndexes()
provider2.select(allAttrs)
sindex = QgsSpatialIndex()
inFeat = QgsFeature()
while provider2.nextFeature(inFeat):
sindex.insertFeature(inFeat)
provider2.rewind()
if nearest < 1: nearest = layer2.featureCount()
else: nearest = nearest
index1 = provider1.fieldNameIndex(field1)
index2 = provider2.fieldNameIndex(field2)
sRs = provider1.crs()
distArea = QgsDistanceArea()
#use srs of the first layer (users should ensure that they are both in the same projection)
#distArea.setSourceSRS(sRs)
f = open(unicode(outPath), "wb")
writer = UnicodeWriter(f)
if matType <> "Standard":
if matType == "Linear":
writer.writerow(["InputID", "TargetID", "Distance"])
else:
writer.writerow(["InputID", "MEAN", "STDDEV", "MIN", "MAX"])
self.linearMatrix(writer, provider1, provider2, index1, index2, nearest, distArea, matType, sindex, progressBar)
else:
self.regularMatrix(writer, provider1, provider2, index1, index2, nearest, distArea, sindex, progressBar)
f.close()
def regularMatrix(self, writer, provider1, provider2, index1, index2, nearest, distArea, sindex, progressBar):
inFeat = QgsFeature()
outFeat = QgsFeature()
inGeom = QgsGeometry()
outGeom = QgsGeometry()
first = True
start = 15.00
add = 85.00 / provider1.featureCount()
while provider1.nextFeature(inFeat):
inGeom = inFeat.geometry()
inID = inFeat.attributeMap()[index1].toString()
if first:
featList = sindex.nearestNeighbor(inGeom.asPoint(), nearest)
first = False
data = ["ID"]
for i in featList:
provider2.featureAtId(int(i), outFeat, True, [index2])
data.append(unicode(outFeat.attributeMap()[index2].toString()))
writer.writerow(data)
data = [unicode(inID)]
for j in featList:
provider2.featureAtId(int(j), outFeat, True)
outGeom = outFeat.geometry()
dist = distArea.measureLine(inGeom.asPoint(), outGeom.asPoint())
data.append(str(float(dist)))
writer.writerow(data)
start = start + add
progressBar.setValue(start)
del writer
def linearMatrix(self, writer, provider1, provider2, index1, index2, nearest, distArea, matType, sindex, progressBar):
inFeat = QgsFeature()
outFeat = QgsFeature()
inGeom = QgsGeometry()
outGeom = QgsGeometry()
start = 15.00
add = 85.00 / provider1.featureCount()
while provider1.nextFeature(inFeat):
inGeom = inFeat.geometry()
inID = inFeat.attributeMap()[index1].toString()
featList = sindex.nearestNeighbor(inGeom.asPoint(), nearest)
distList = []
vari = 0.00
for i in featList:
provider2.featureAtId(int(i), outFeat, True, [index2])
outID = outFeat.attributeMap()[index2].toString()
outGeom = outFeat.geometry()
dist = distArea.measureLine(inGeom.asPoint(), outGeom.asPoint())
if dist > 0:
if matType == "Linear": writer.writerow([unicode(inID), unicode(outID), str(dist)])
else: distList.append(float(dist))
if matType == "Summary":
mean = sum(distList) / len(distList)
for i in distList:
vari = vari + ((i - mean)*(i - mean))
vari = sqrt(vari / len(distList))
writer.writerow([unicode(inID), str(mean), str(vari), str(min(distList)), str(max(distList))])
start = start + add
progressBar.setValue(start)
del writer