Question

我编写了这段代码，以使用pyqgis在多边形内选择点。

using System.IO;

仅当我的多边形shapefile仅由一个要素合成时，该方法才起作用，否则会出现此错误

string str = @"c:\users\john\desktop\test.txt";
Console.WriteLine(Path.GetFileName(str));

我试图以此修改最后一部分：

polygonFile = '/home/polygon.shp'
pointFile = '/home/points.shp'

polygonLayer = QgsVectorLayer(polygonFile, 'poligoni', 'ogr')
pointLayer = QgsVectorLayer(pointFile, 'punti', 'ogr')

polygonFeatureList = [plfeat for plfeat in polygonLayer.getFeatures()]
pointFeatureList =  [ptfeat for ptfeat in pointLayer.getFeatures()]

polygonFeatureNumber = polygonLayer.featureCount()
pointFeatureNumber = pointLayer.featureCount()

QgsMapLayerRegistry.instance().addMapLayer(polygonLayer)
QgsMapLayerRegistry.instance().addMapLayer(pointLayer)

for ptfeat in pointFeatureList:
    ptGeometry = ptfeat.geometry()
    for plfeat in polygonFeatureList:
        plGeometry = plfeat.geometry()
        if plGeometry.contains(ptGeometry):
            pointLayer.select(ptfeat.id)

但是这次我遇到这种错误

TypeError: arguments did not match any overloaded call:
  QgsVectorLayer.select(QgsRectangle, bool): argument 1 has unexpected type 'builtin_function_or_method'
  QgsVectorLayer.select(int): argument 1 has unexpected type 'builtin_function_or_method'
  QgsVectorLayer.select(unknown-type): argument 1 has unexpected type 'builtin_function_or_method'

到目前为止，我还没有找到在空间查询中正确使用“选择”功能的方法。

Answer 1

我找到了两种解决方案

这是第一个

polygonFile = '/path/poligoni.shp'
pointFile = '/path/punti.shp'

polygonLayer = QgsVectorLayer(polygonFile, 'poligoni', 'ogr')
pointLayer = QgsVectorLayer(pointFile, 'punti', 'ogr')

polygonFeatureList = [plFeat for plFeat in polygonLayer.getFeatures()]
pointFeatureList = [ptFeat for ptFeat in pointLayer.getFeatures()]

QgsMapLayerRegistry.instance().addMapLayer(polygonLayer)
QgsMapLayerRegistry.instance().addMapLayer(pointLayer)

for ptFeat in pointFeatureList:
    ptGeom = ptFeat.geometry()
    for plFeat in polygonFeatureList:
        plGeom = plFeat.geometry()
        if plGeom.contains(ptGeom):
            pointLayer.select(ptFeat.id())

这是第二个解决方案

import processing

polygonFile = '/path/poligoni.shp'
pointFile = '/path/punti.shp'

polygonLayer = QgsVectorLayer(polygonFile, 'poligoni', 'ogr')
pointLayer = QgsVectorLayer(pointFile, 'punti', 'ogr')

polygonFeatureList = [plFeat for plFeat in polygonLayer.getFeatures()]
pointFeatureList = [ptFeat for ptFeat in pointLayer.getFeatures()]

QgsMapLayerRegistry.instance().addMapLayer(polygonLayer)
QgsMapLayerRegistry.instance().addMapLayer(pointLayer)

processing.runalg('qgis:selectbylocation', pointLayer, polygonLayer, u'contains', 0, 0)

如何在多个多边形矢量层的区域内选择点？

1 个答案: