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Python QgsFeatureRequest.flags方法代码示例

本文整理汇总了Python中qgis.core.QgsFeatureRequest.flags方法的典型用法代码示例。如果您正苦于以下问题:Python QgsFeatureRequest.flags方法的具体用法?Python QgsFeatureRequest.flags怎么用?Python QgsFeatureRequest.flags使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在qgis.core.QgsFeatureRequest的用法示例。


在下文中一共展示了QgsFeatureRequest.flags方法的4个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Python代码示例。

示例1: processAlgorithm

# 需要导入模块: from qgis.core import QgsFeatureRequest [as 别名]
# 或者: from qgis.core.QgsFeatureRequest import flags [as 别名]
    def processAlgorithm(self, feedback):
        layer = dataobjects.getObjectFromUri(
            self.getParameterValue(self.INPUT_VECTOR))
        startPoints = dataobjects.getObjectFromUri(
            self.getParameterValue(self.START_POINTS))
        strategy = self.getParameterValue(self.STRATEGY)
        travelCost = self.getParameterValue(self.TRAVEL_COST)

        directionFieldName = self.getParameterValue(self.DIRECTION_FIELD)
        forwardValue = self.getParameterValue(self.VALUE_FORWARD)
        backwardValue = self.getParameterValue(self.VALUE_BACKWARD)
        bothValue = self.getParameterValue(self.VALUE_BOTH)
        defaultDirection = self.getParameterValue(self.DEFAULT_DIRECTION)
        bothValue = self.getParameterValue(self.VALUE_BOTH)
        defaultDirection = self.getParameterValue(self.DEFAULT_DIRECTION)
        speedFieldName = self.getParameterValue(self.SPEED_FIELD)
        defaultSpeed = self.getParameterValue(self.DEFAULT_SPEED)
        tolerance = self.getParameterValue(self.TOLERANCE)

        fields = QgsFields()
        fields.append(QgsField('type', QVariant.String, '', 254, 0))
        fields.append(QgsField('start', QVariant.String, '', 254, 0))

        feat = QgsFeature()
        feat.setFields(fields)

        writerPoints = self.getOutputFromName(
            self.OUTPUT_POINTS).getVectorWriter(
                fields,
                QgsWkbTypes.MultiPoint,
                layer.crs())

        writerPolygons = self.getOutputFromName(
            self.OUTPUT_POLYGON).getVectorWriter(
                fields,
                QgsWkbTypes.Polygon,
                layer.crs())

        directionField = -1
        if directionFieldName is not None:
            directionField = layer.fields().lookupField(directionFieldName)
        speedField = -1
        if speedFieldName is not None:
            speedField = layer.fields().lookupField(speedFieldName)

        director = QgsVectorLayerDirector(layer,
                                          directionField,
                                          forwardValue,
                                          backwardValue,
                                          bothValue,
                                          defaultDirection)

        distUnit = iface.mapCanvas().mapSettings().destinationCrs().mapUnits()
        multiplier = QgsUnitTypes.fromUnitToUnitFactor(distUnit, QgsUnitTypes.DistanceMeters)
        if strategy == 0:
            strategy = QgsNetworkDistanceStrategy()
        else:
            strategy = QgsNetworkSpeedStrategy(speedField,
                                               defaultSpeed,
                                               multiplier * 1000.0 / 3600.0)

        director.addStrategy(strategy)
        builder = QgsGraphBuilder(iface.mapCanvas().mapSettings().destinationCrs(),
                                  iface.mapCanvas().hasCrsTransformEnabled(),
                                  tolerance)

        feedback.pushInfo(self.tr('Loading start points...'))
        request = QgsFeatureRequest()
        request.setFlags(request.flags() ^ QgsFeatureRequest.SubsetOfAttributes)
        features = vector.features(startPoints, request)
        points = []
        for f in features:
            points.append(f.geometry().asPoint())

        feedback.pushInfo(self.tr('Building graph...'))
        snappedPoints = director.makeGraph(builder, points)

        feedback.pushInfo(self.tr('Calculating service areas...'))
        graph = builder.graph()

        vertices = []
        upperBoundary = []
        lowerBoundary = []
        total = 100.0 / len(snappedPoints)
        for i, p in enumerate(snappedPoints):
            idxStart = graph.findVertex(snappedPoints[i])
            origPoint = points[i].toString()

            tree, cost = QgsGraphAnalyzer.dijkstra(graph, idxStart, 0)
            for j, v in enumerate(cost):
                if v > travelCost and tree[j] != -1:
                    vertexId = graph.edge(tree[j]).outVertex()
                    if cost[vertexId] <= travelCost:
                        vertices.append(j)

            for j in vertices:
                upperBoundary.append(graph.vertex(graph.edge(tree[j]).inVertex()).point())
                lowerBoundary.append(graph.vertex(graph.edge(tree[j]).outVertex()).point())

            geomUpper = QgsGeometry.fromMultiPoint(upperBoundary)
#.........这里部分代码省略.........
开发者ID:Gustry,项目名称:QGIS,代码行数:103,代码来源:ServiceAreaFromLayer.py

示例2: processAlgorithm

# 需要导入模块: from qgis.core import QgsFeatureRequest [as 别名]
# 或者: from qgis.core.QgsFeatureRequest import flags [as 别名]
    def processAlgorithm(self, parameters, context, feedback):
        network = self.parameterAsSource(parameters, self.INPUT, context)
        startPoints = self.parameterAsSource(parameters, self.START_POINTS, context)
        endPoint = self.parameterAsPoint(parameters, self.END_POINT, context, network.sourceCrs())
        strategy = self.parameterAsEnum(parameters, self.STRATEGY, context)

        directionFieldName = self.parameterAsString(parameters, self.DIRECTION_FIELD, context)
        forwardValue = self.parameterAsString(parameters, self.VALUE_FORWARD, context)
        backwardValue = self.parameterAsString(parameters, self.VALUE_BACKWARD, context)
        bothValue = self.parameterAsString(parameters, self.VALUE_BOTH, context)
        defaultDirection = self.parameterAsEnum(parameters, self.DEFAULT_DIRECTION, context)
        speedFieldName = self.parameterAsString(parameters, self.SPEED_FIELD, context)
        defaultSpeed = self.parameterAsDouble(parameters, self.DEFAULT_SPEED, context)
        tolerance = self.parameterAsDouble(parameters, self.TOLERANCE, context)

        fields = QgsFields()
        fields.append(QgsField('start', QVariant.String, '', 254, 0))
        fields.append(QgsField('end', QVariant.String, '', 254, 0))
        fields.append(QgsField('cost', QVariant.Double, '', 20, 7))

        feat = QgsFeature()
        feat.setFields(fields)

        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
                                               fields, QgsWkbTypes.LineString, network.sourceCrs())

        directionField = -1
        if directionFieldName:
            directionField = network.fields().lookupField(directionFieldName)
        speedField = -1
        if speedFieldName:
            speedField = network.fields().lookupField(speedFieldName)

        director = QgsVectorLayerDirector(network,
                                          directionField,
                                          forwardValue,
                                          backwardValue,
                                          bothValue,
                                          defaultDirection)

        distUnit = context.project().crs().mapUnits()
        multiplier = QgsUnitTypes.fromUnitToUnitFactor(distUnit, QgsUnitTypes.DistanceMeters)
        if strategy == 0:
            strategy = QgsNetworkDistanceStrategy()
        else:
            strategy = QgsNetworkSpeedStrategy(speedField,
                                               defaultSpeed,
                                               multiplier * 1000.0 / 3600.0)
            multiplier = 3600

        director.addStrategy(strategy)
        builder = QgsGraphBuilder(network.sourceCrs(),
                                  True,
                                  tolerance)

        feedback.pushInfo(self.tr('Loading start points...'))
        request = QgsFeatureRequest()
        request.setFlags(request.flags() ^ QgsFeatureRequest.SubsetOfAttributes)
        request.setDestinationCrs(network.sourceCrs())
        features = startPoints.getFeatures(request)
        total = 100.0 / startPoints.featureCount() if startPoints.featureCount() else 0

        points = [endPoint]
        for current, f in enumerate(features):
            if feedback.isCanceled():
                break

            points.append(f.geometry().asPoint())
            feedback.setProgress(int(current * total))

        feedback.pushInfo(self.tr('Building graph...'))
        snappedPoints = director.makeGraph(builder, points, feedback)

        feedback.pushInfo(self.tr('Calculating shortest paths...'))
        graph = builder.graph()

        idxEnd = graph.findVertex(snappedPoints[0])
        route = []

        nPoints = len(snappedPoints)
        total = 100.0 / nPoints if nPoints else 1
        for i in range(1, nPoints + 1):
            if feedback.isCanceled():
                break

            idxStart = graph.findVertex(snappedPoints[i])
            tree, cost = QgsGraphAnalyzer.dijkstra(graph, idxStart, 0)

            if tree[idxEnd] == -1:
                msg = self.tr('There is no route from start point ({}) to end point ({}).'.format(points[i].toString(), endPoint.toString()))
                feedback.setProgressText(msg)
                QgsMessageLog.logMessage(msg, self.tr('Processing'), QgsMessageLog.WARNING)
                continue

            cost = 0.0
            current = idxEnd
            while current != idxStart:
                cost += graph.edge(tree[current]).cost(0)
                route.append(graph.vertex(graph.edge(tree[current]).inVertex()).point())
                current = graph.edge(tree[current]).outVertex()
#.........这里部分代码省略.........
开发者ID:giohappy,项目名称:QGIS,代码行数:103,代码来源:ShortestPathLayerToPoint.py

示例3: processAlgorithm

# 需要导入模块: from qgis.core import QgsFeatureRequest [as 别名]
# 或者: from qgis.core.QgsFeatureRequest import flags [as 别名]
    def processAlgorithm(self, parameters, context, feedback):
        network = self.parameterAsSource(parameters, self.INPUT, context)
        startPoints = self.parameterAsSource(parameters, self.START_POINTS, context)
        strategy = self.parameterAsEnum(parameters, self.STRATEGY, context)
        travelCost = self.parameterAsDouble(parameters, self.TRAVEL_COST, context)

        directionFieldName = self.parameterAsString(parameters, self.DIRECTION_FIELD, context)
        forwardValue = self.parameterAsString(parameters, self.VALUE_FORWARD, context)
        backwardValue = self.parameterAsString(parameters, self.VALUE_BACKWARD, context)
        bothValue = self.parameterAsString(parameters, self.VALUE_BOTH, context)
        defaultDirection = self.parameterAsEnum(parameters, self.DEFAULT_DIRECTION, context)
        speedFieldName = self.parameterAsString(parameters, self.SPEED_FIELD, context)
        defaultSpeed = self.parameterAsDouble(parameters, self.DEFAULT_SPEED, context)
        tolerance = self.parameterAsDouble(parameters, self.TOLERANCE, context)

        fields = QgsFields()
        fields.append(QgsField('type', QVariant.String, '', 254, 0))
        fields.append(QgsField('start', QVariant.String, '', 254, 0))

        feat = QgsFeature()
        feat.setFields(fields)

        directionField = -1
        if directionFieldName:
            directionField = network.fields().lookupField(directionFieldName)
        speedField = -1
        if speedFieldName:
            speedField = network.fields().lookupField(speedFieldName)

        director = QgsVectorLayerDirector(network,
                                          directionField,
                                          forwardValue,
                                          backwardValue,
                                          bothValue,
                                          defaultDirection)

        distUnit = context.project().crs().mapUnits()
        multiplier = QgsUnitTypes.fromUnitToUnitFactor(distUnit, QgsUnitTypes.DistanceMeters)
        if strategy == 0:
            strategy = QgsNetworkDistanceStrategy()
        else:
            strategy = QgsNetworkSpeedStrategy(speedField,
                                               defaultSpeed,
                                               multiplier * 1000.0 / 3600.0)

        director.addStrategy(strategy)
        builder = QgsGraphBuilder(network.sourceCrs(),
                                  True,
                                  tolerance)

        feedback.pushInfo(self.tr('Loading start points...'))
        request = QgsFeatureRequest()
        request.setFlags(request.flags() ^ QgsFeatureRequest.SubsetOfAttributes)
        request.setDestinationCrs(network.sourceCrs())
        features = startPoints.getFeatures(request)
        total = 100.0 / startPoints.featureCount() if startPoints.featureCount() else 0

        points = []
        for current, f in enumerate(features):
            if feedback.isCanceled():
                break

            points.append(f.geometry().asPoint())
            feedback.setProgress(int(current * total))

        feedback.pushInfo(self.tr('Building graph...'))
        snappedPoints = director.makeGraph(builder, points, feedback)

        feedback.pushInfo(self.tr('Calculating service areas...'))
        graph = builder.graph()

        (sink, dest_id) = self.parameterAsSink(parameters, self.OUTPUT, context,
                                               fields, QgsWkbTypes.MultiPoint, network.sourceCrs())

        vertices = []
        upperBoundary = []
        lowerBoundary = []
        total = 100.0 / len(snappedPoints) if snappedPoints else 1
        for i, p in enumerate(snappedPoints):
            if feedback.isCanceled():
                break

            idxStart = graph.findVertex(snappedPoints[i])
            origPoint = points[i].toString()

            tree, cost = QgsGraphAnalyzer.dijkstra(graph, idxStart, 0)
            for j, v in enumerate(cost):
                if v > travelCost and tree[j] != -1:
                    vertexId = graph.edge(tree[j]).outVertex()
                    if cost[vertexId] <= travelCost:
                        vertices.append(j)

            for j in vertices:
                upperBoundary.append(graph.vertex(graph.edge(tree[j]).inVertex()).point())
                lowerBoundary.append(graph.vertex(graph.edge(tree[j]).outVertex()).point())

            geomUpper = QgsGeometry.fromMultiPoint(upperBoundary)
            geomLower = QgsGeometry.fromMultiPoint(lowerBoundary)

            feat.setGeometry(geomUpper)
#.........这里部分代码省略.........
开发者ID:GeoCat,项目名称:QGIS,代码行数:103,代码来源:ServiceAreaFromLayer.py

示例4: layerToVolumeTxt

# 需要导入模块: from qgis.core import QgsFeatureRequest [as 别名]
# 或者: from qgis.core.QgsFeatureRequest import flags [as 别名]
def layerToVolumeTxt(layer, project):
    ''' extract layer column to have only traffic count for the algoritm
    This utility is intended to generate v_traffic.txt
    Column of the layer are get from the project. If a column is not specified
    it will filled with 0 value
    '''
    # get out filename 
    confFileName = project.fileName()
    projectPath = os.path.dirname(confFileName)

    outFileName = project.value('General.InputFileDefinition/TrafficVolume', '')
    if not outFileName:
        raise Exception('No General.InputFileDefinition/TrafficVolume filename has bee specified')
    
    if not os.path.isabs( outFileName ):
        outFileName = os.path.join(projectPath, outFileName)
    
    # get columns to estract
    columnRoadType = project.value('InputNetwork/columnRoadType', '')
    columnRoadLenght = project.value('InputNetwork/columnRoadLenght', '')
    columnRoadSlope = project.value('InputNetwork/columnRoadSlope', '')
    
    columnPassengerCars = project.value('VehicleCountSpeed/columnPassengerCars', '')
    columnLightDutyVehicle = project.value('VehicleCountSpeed/columnLightDutyVehicle', '')
    columnHeavyDutyVechicle = project.value('VehicleCountSpeed/columnHeavyDutyVechicle', '')
    columnUrbanBuses = project.value('VehicleCountSpeed/columnUrbanBuses', '')
    columnMotorcycle = project.value('VehicleCountSpeed/columnMotorcycle', '')
    columnCouch = project.value('VehicleCountSpeed/columnCouch', '')
    columnAverageSpeed = project.value('VehicleCountSpeed/columnAverageSpeed', '')
    
    fields = ['id', 
               columnRoadType, 
               columnPassengerCars, 
               columnLightDutyVehicle, 
               columnHeavyDutyVechicle, 
               columnUrbanBuses,
               columnCouch,
               columnMotorcycle,
               columnAverageSpeed,
               columnRoadLenght,
               columnRoadSlope
               ]
    # create out file
    with open(outFileName, 'w') as outFile:
        
        # print header
        template = '{}\t{}\t{}\t{}\t{}\t{}\t{}\t{}\t{}\t{:.5f}\t{:.5f}'
        header = 'ID\tTYPE\tPC\tLDV\tHDV\tBUS\tCOACHES\tMOTO\tSPEED\tLENGHT\tGRAD'
        print(header, file=outFile)
        
        # get all records
        fieldsToRetrieve = [x for x in fields if x] # remove not requested fields
        request = QgsFeatureRequest()
        request.setSubsetOfAttributes(fieldsToRetrieve, layer.pendingFields())
        request.setFlags( request.flags() | QgsFeatureRequest.NoGeometry)
        
        for feature in layer.getFeatures( request ):
            values = []
            for field in fields:
                value = 0 # defauklt value in case the column is not present or not requested
                try:
                    value = feature.attribute(field)
                except:
                    pass
                values.append( value )
             
            # then print feature
            print(template.format(*values), file=outFile)
开发者ID:QTrafficmodel,项目名称:QTraffic,代码行数:70,代码来源:traffic_volume_utils.py


注:本文中的qgis.core.QgsFeatureRequest.flags方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。