def polygon_elongation(polygon: QgsPolygon): ''' Compute the elongation of a rectangle, equals to the ratio length / width. If the polygon in parameter has a number of coordinates different from 5, the value -1.0 is returned. ''' # if len(polygon.vertices()) != 5: if _geometry_num_vertices(polygon) != 5: return -1.0 vertices = _geometry_vertices(polygon, 2) # v0 = QgsPoint(vertices[0]) # v1 = QgsPoint(vertices[1]) # v2 = QgsPoint(vertices[2]) v0 = QgsPoint(vertices[0].x(), vertices[0].y()) v1 = QgsPoint(vertices[1].x(), vertices[1].y()) v2 = QgsPoint(vertices[2].x(), vertices[2].y()) length = v0.distance(v1.x(), v1.y()) length2 = v1.distance(v2.x(), v2.y()) if length == length2: return length / length2 return lentgh2 / lentgh
def testMeasureLineProjected(self): # +-+ # | | # +-+ + # test setting/getting the source CRS da_3068 = QgsDistanceArea() da_wsg84 = QgsDistanceArea() da_3068.setSourceCrs(QgsCoordinateReferenceSystem.fromOgcWmsCrs('EPSG:3068')) if (da_3068.sourceCrs().isGeographic()): da_3068.setEllipsoid(da_3068.sourceCrs().ellipsoidAcronym()) print(("setting [{}] srid [{}] description [{}]".format(u'Soldner Berlin', da_3068.sourceCrs().authid(), da_3068.sourceCrs().description()))) self.assertEqual(da_3068.sourceCrs().authid(), 'EPSG:3068') da_wsg84.setSourceCrs(QgsCoordinateReferenceSystem.fromOgcWmsCrs('EPSG:4326')) if (da_wsg84.sourceCrs().isGeographic()): da_wsg84.setEllipsoid(da_wsg84.sourceCrs().ellipsoidAcronym()) self.assertEqual(da_wsg84.sourceCrs().authid(), 'EPSG:4326') print(("setting [{}] srid [{}] description [{}] isGeographic[{}]".format(u'Wsg84', da_wsg84.sourceCrs().authid(), da_wsg84.sourceCrs().description(), da_wsg84.sourceCrs().isGeographic()))) # print(("-- projectionAcronym[{}] ellipsoidAcronym[{}] toWkt[{}] mapUnits[{}] toProj4[{}]".format(da_wsg84.sourceCrs().projectionAcronym(),da_wsg84.sourceCrs().ellipsoidAcronym(), da_wsg84.sourceCrs().toWkt(),da_wsg84.sourceCrs().mapUnits(),da_wsg84.sourceCrs().toProj4()))) print(("Testing Position change for[{}] years[{}]".format(u'Ampelanlage - Potsdamer Platz, Verkehrsinsel', u'1924 and 1998'))) # 1924-10-24 SRID=3068;POINT(23099.49 20296.69) # 1924-10-24 SRID=4326;POINT(13.37650707988041 52.50952361017194) # 1998-10-02 SRID=3068;POINT(23082.30 20267.80) # 1998-10-02 SRID=4326;POINT(13.37625537334001 52.50926345498337) # values returned by spatialite point_soldner_1924 = QgsPoint(23099.49, 20296.69) point_soldner_1998 = QgsPoint(23082.30, 20267.80) distance_soldner_meters = 33.617379 azimuth_soldner_1924 = 3.678339 # ST_Transform(point_soldner_1924,point_soldner_1998,4326) point_wsg84_1924 = QgsPoint(13.37650707988041, 52.50952361017194) point_wsg84_1998 = QgsPoint(13.37625537334001, 52.50926345498337) # ST_Distance(point_wsg84_1924,point_wsg84_1998,1) distance_wsg84_meters = 33.617302 # ST_Distance(point_wsg84_1924,point_wsg84_1998) # distance_wsg84_mapunits=0.000362 distance_wsg84_mapunits_format = QgsDistanceArea.formatDistance(0.000362, 7, QgsUnitTypes.DistanceDegrees, True) # ST_Azimuth(point_wsg84_1924,point_wsg84_1998) azimuth_wsg84_1924 = 3.674878 # ST_Azimuth(point_wsg84_1998,point_wsg84_1998) azimuth_wsg84_1998 = 0.533282 # ST_Project(point_wsg84_1924,33.617302,3.674878) # SRID=4326;POINT(13.37625537318728 52.50926345503591) point_soldner_1998_project = QgsPoint(13.37625537318728, 52.50926345503591) # ST_Project(point_wsg84_1998,33.617302,0.533282) # SRID=4326;POINT(13.37650708009255 52.50952361009799) point_soldner_1924_project = QgsPoint(13.37650708009255, 52.50952361009799) distance_qpoint = point_soldner_1924.distance(point_soldner_1998) azimuth_qpoint = point_soldner_1924.azimuth(point_soldner_1998) point_soldner_1998_result = point_soldner_1924.project(distance_qpoint, azimuth_qpoint) point_soldner_1924_result = QgsPoint(0, 0) point_soldner_1998_result = QgsPoint(0, 0) # Test meter based projected point from point_1924 to point_1998 length_1998_mapunits, point_soldner_1998_result = da_3068.measureLineProjected(point_soldner_1924, distance_soldner_meters, azimuth_qpoint) self.assertEqual(point_soldner_1998_result.toString(6), point_soldner_1998.toString(6)) # Test degree based projected point from point_1924 1 meter due East point_wsg84_meter_result = QgsPoint(0, 0) point_wsg84_1927_meter = QgsPoint(13.37652180838435, 52.50952361017102) length_meter_mapunits, point_wsg84_meter_result = da_wsg84.measureLineProjected(point_wsg84_1924, 1.0, (math.pi / 2)) self.assertEqual(QgsDistanceArea.formatDistance(length_meter_mapunits, 7, QgsUnitTypes.DistanceDegrees, True), '0.0000147 deg') self.assertEqual(point_wsg84_meter_result.toString(7), point_wsg84_1927_meter.toString(7)) point_wsg84_1998_result = QgsPoint(0, 0) length_1928_mapunits, point_wsg84_1998_result = da_wsg84.measureLineProjected(point_wsg84_1924, distance_wsg84_meters, azimuth_wsg84_1924) self.assertEqual(QgsDistanceArea.formatDistance(length_1928_mapunits, 7, QgsUnitTypes.DistanceDegrees, True), distance_wsg84_mapunits_format) self.assertEqual(point_wsg84_1998_result.toString(7), point_wsg84_1998.toString(7))