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Python QgsCoordinateReferenceSystem.srsid方法代码示例

本文整理汇总了Python中qgis.core.QgsCoordinateReferenceSystem.srsid方法的典型用法代码示例。如果您正苦于以下问题：Python QgsCoordinateReferenceSystem.srsid方法的具体用法？Python QgsCoordinateReferenceSystem.srsid怎么用？Python QgsCoordinateReferenceSystem.srsid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类qgis.core.QgsCoordinateReferenceSystem的用法示例。


在下文中一共展示了QgsCoordinateReferenceSystem.srsid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: test_ExpressionFieldEllipsoidLengthCalculation

# 需要导入模块: from qgis.core import QgsCoordinateReferenceSystem [as 别名]
# 或者: from qgis.core.QgsCoordinateReferenceSystem import srsid [as 别名]
    def test_ExpressionFieldEllipsoidLengthCalculation(self):
        #create a temporary layer
        temp_layer = QgsVectorLayer("LineString?crs=epsg:3111&field=pk:int", "vl", "memory")
        self.assertTrue(temp_layer.isValid())
        f1 = QgsFeature(temp_layer.dataProvider().fields(), 1)
        f1.setAttribute("pk", 1)
        f1.setGeometry(QgsGeometry.fromPolyline([QgsPoint(2484588, 2425722), QgsPoint(2482767, 2398853)]))
        temp_layer.dataProvider().addFeatures([f1])

        # set project CRS and ellipsoid
        srs = QgsCoordinateReferenceSystem(3111, QgsCoordinateReferenceSystem.EpsgCrsId)
        QgsProject.instance().writeEntry("SpatialRefSys", "/ProjectCRSProj4String", srs.toProj4())
        QgsProject.instance().writeEntry("SpatialRefSys", "/ProjectCRSID", srs.srsid())
        QgsProject.instance().writeEntry("SpatialRefSys", "/ProjectCrs", srs.authid())
        QgsProject.instance().writeEntry("Measure", "/Ellipsoid", "WGS84")
        QgsProject.instance().writeEntry("Measurement", "/DistanceUnits", QgsUnitTypes.encodeUnit(QGis.Meters))

        idx = temp_layer.addExpressionField('$length', QgsField('length', QVariant.Double))  # NOQA

        # check value
        f = temp_layer.getFeatures().next()
        expected = 26932.156
        self.assertAlmostEqual(f['length'], expected, 3)

        # change project length unit, check calculation respects unit
        QgsProject.instance().writeEntry("Measurement", "/DistanceUnits", QgsUnitTypes.encodeUnit(QGis.Feet))
        f = temp_layer.getFeatures().next()
        expected = 88360.0918635
        self.assertAlmostEqual(f['length'], expected, 3)
开发者ID:Clayton-Davis，项目名称:QGIS，代码行数:31，代码来源:test_qgsvectorlayer.py

示例2: test_ExpressionFieldEllipsoidAreaCalculation

# 需要导入模块: from qgis.core import QgsCoordinateReferenceSystem [as 别名]
# 或者: from qgis.core.QgsCoordinateReferenceSystem import srsid [as 别名]
    def test_ExpressionFieldEllipsoidAreaCalculation(self):
        #create a temporary layer
        temp_layer = QgsVectorLayer("Polygon?crs=epsg:3111&field=pk:int", "vl", "memory")
        self.assertTrue(temp_layer.isValid())
        f1 = QgsFeature(temp_layer.dataProvider().fields(), 1)
        f1.setAttribute("pk", 1)
        f1.setGeometry(QgsGeometry.fromPolygon([[QgsPoint(2484588, 2425722), QgsPoint(2482767, 2398853), QgsPoint(2520109, 2397715), QgsPoint(2520792, 2425494), QgsPoint(2484588, 2425722)]]))
        temp_layer.dataProvider().addFeatures([f1])

        # set project CRS and ellipsoid
        srs = QgsCoordinateReferenceSystem(3111, QgsCoordinateReferenceSystem.EpsgCrsId)
        QgsProject.instance().writeEntry("SpatialRefSys", "/ProjectCRSProj4String", srs.toProj4())
        QgsProject.instance().writeEntry("SpatialRefSys", "/ProjectCRSID", srs.srsid())
        QgsProject.instance().writeEntry("SpatialRefSys", "/ProjectCrs", srs.authid())
        QgsProject.instance().writeEntry("Measure", "/Ellipsoid", "WGS84")
        QgsProject.instance().writeEntry("Measurement", "/AreaUnits", QgsUnitTypes.encodeUnit(QgsUnitTypes.SquareMeters))

        idx = temp_layer.addExpressionField('$area', QgsField('area', QVariant.Double))  # NOQA

        # check value
        f = temp_layer.getFeatures().next()
        expected = 1009089817.0
        self.assertAlmostEqual(f['area'], expected, delta=1.0)

        # change project area unit, check calculation respects unit
        QgsProject.instance().writeEntry("Measurement", "/AreaUnits", QgsUnitTypes.encodeUnit(QgsUnitTypes.SquareMiles))
        f = temp_layer.getFeatures().next()
        expected = 389.6117565069
        self.assertAlmostEqual(f['area'], expected, 3)
开发者ID:Clayton-Davis，项目名称:QGIS，代码行数:31，代码来源:test_qgsvectorlayer.py

示例3: testCrs

# 需要导入模块: from qgis.core import QgsCoordinateReferenceSystem [as 别名]
# 或者: from qgis.core.QgsCoordinateReferenceSystem import srsid [as 别名]
    def testCrs(self):
        # test setting/getting the source CRS
        da = QgsDistanceArea()

        # try setting using a CRS object
        crs = QgsCoordinateReferenceSystem(3111, QgsCoordinateReferenceSystem.EpsgCrsId)
        da.setSourceCrs(crs, QgsProject.instance().transformContext())
        self.assertEqual(da.sourceCrs().srsid(), crs.srsid())
开发者ID:anitagraser，项目名称:QGIS，代码行数:10，代码来源:test_qgsdistancearea.py

示例4: testCrs

# 需要导入模块: from qgis.core import QgsCoordinateReferenceSystem [as 别名]
# 或者: from qgis.core.QgsCoordinateReferenceSystem import srsid [as 别名]
    def testCrs(self):
        # test setting/getting the source CRS
        da = QgsDistanceArea()

        # try setting using a crs id
        da.setSourceCrs(3452)
        self.assertEqual(da.sourceCrsId(), 3452)

        # try setting using a CRS object
        crs = QgsCoordinateReferenceSystem(3111, QgsCoordinateReferenceSystem.EpsgCrsId)
        da.setSourceCrs(crs)
        self.assertEqual(da.sourceCrsId(), crs.srsid())
开发者ID:grizonnetm，项目名称:QGIS，代码行数:14，代码来源:test_qgsdistancearea.py


注：本文中的qgis.core.QgsCoordinateReferenceSystem.srsid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。