def getCrs(self, srid):
if not self.has_spatial:
return QgsCoordinateReferenceSystem()
try:
c = self._execute(None, "SELECT proj4text FROM spatial_ref_sys WHERE srid = '%d'" % srid)
except DbError:
return QgsCoordinateReferenceSystem()
res = self._fetchone(c)
self._close_cursor(c)
if res is None:
return QgsCoordinateReferenceSystem()
proj4text = res[0]
crs = QgsCoordinateReferenceSystem.fromProj(proj4text)
return crs
def _recompute_area_radius_centroid(self):
geometry = self.geometry
crs = QgsCoordinateReferenceSystem.fromProj(self.crs)
distance_area_calculator = QgsDistanceArea()
distance_area_calculator.setSourceCrs(crs, QgsCoordinateTransformContext())
if not crs.isGeographic():
# we want to keep the same units as the coordinates
# (and setEllipsoid will make measureArea return meters)
distance_area_calculator.setEllipsoid("WGS84")
# recompute area
self._area = distance_area_calculator.measureArea(geometry)
# recompute radius
if self._area == 0:
self._radius = 0
else:
self._radius = math.sqrt(self._area / math.pi)
# recompute centroid
centroid = geometry.centroid().asPoint()
self._cx = centroid.x()
self._cy = centroid.y()
def testCreateMemoryLayer(self):
"""
Test QgsMemoryProviderUtils.createMemoryLayer()
"""
# no fields
layer = QgsMemoryProviderUtils.createMemoryLayer(
'my name', QgsFields())
self.assertTrue(layer.isValid())
self.assertEqual(layer.name(), 'my name')
self.assertTrue(layer.fields().isEmpty())
# similar layers should have unique sources
layer2 = QgsMemoryProviderUtils.createMemoryLayer(
'my name', QgsFields())
self.assertNotEqual(layer.source(), layer2.source())
# geometry type
layer = QgsMemoryProviderUtils.createMemoryLayer(
'my name', QgsFields(), QgsWkbTypes.Point)
self.assertTrue(layer.isValid())
self.assertEqual(layer.wkbType(), QgsWkbTypes.Point)
layer = QgsMemoryProviderUtils.createMemoryLayer(
'my name', QgsFields(), QgsWkbTypes.PolygonZM)
self.assertTrue(layer.isValid())
self.assertEqual(layer.wkbType(), QgsWkbTypes.PolygonZM)
# crs
layer = QgsMemoryProviderUtils.createMemoryLayer(
'my name', QgsFields(), QgsWkbTypes.PolygonZM,
QgsCoordinateReferenceSystem.fromEpsgId(3111))
self.assertTrue(layer.isValid())
self.assertEqual(layer.wkbType(), QgsWkbTypes.PolygonZM)
self.assertTrue(layer.crs().isValid())
self.assertEqual(layer.crs().authid(), 'EPSG:3111')
# custom CRS
crs = QgsCoordinateReferenceSystem.fromProj(
'+proj=qsc +lat_0=0 +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +units=m +no_defs'
)
layer = QgsMemoryProviderUtils.createMemoryLayer(
'my name', QgsFields(), QgsWkbTypes.PolygonZM, crs)
self.assertTrue(layer.isValid())
self.assertTrue(layer.crs().isValid())
self.assertEqual(
layer.crs().toProj(),
'+proj=qsc +lat_0=0 +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +units=m +no_defs +type=crs'
)
# clone it, just to check
layer2 = layer.clone()
self.assertEqual(
layer2.crs().toProj(),
'+proj=qsc +lat_0=0 +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +units=m +no_defs +type=crs'
)
# fields
fields = QgsFields()
fields.append(QgsField("string", QVariant.String))
fields.append(QgsField("long", QVariant.LongLong))
fields.append(QgsField("double", QVariant.Double))
fields.append(QgsField("integer", QVariant.Int))
fields.append(QgsField("date", QVariant.Date))
fields.append(QgsField("datetime", QVariant.DateTime))
fields.append(QgsField("time", QVariant.Time))
fields.append(QgsField("#complex_name", QVariant.String))
fields.append(QgsField("complex/name", QVariant.String))
fields.append(QgsField("binaryfield", QVariant.ByteArray))
fields.append(QgsField("boolfield", QVariant.Bool))
fields.append(QgsField("vallist", QVariant.List, subType=QVariant.Int))
fields.append(
QgsField("stringlist",
QVariant.StringList,
subType=QVariant.String))
fields.append(
QgsField("stringlist2", QVariant.List, subType=QVariant.String))
fields.append(
QgsField("reallist", QVariant.List, subType=QVariant.Double))
fields.append(
QgsField("longlist", QVariant.List, subType=QVariant.LongLong))
fields.append(QgsField("dict", QVariant.Map))
layer = QgsMemoryProviderUtils.createMemoryLayer('my name', fields)
self.assertTrue(layer.isValid())
self.assertFalse(layer.fields().isEmpty())
self.assertEqual(len(layer.fields()), len(fields))
for i in range(len(fields)):
self.assertEqual(layer.fields()[i].name(), fields[i].name())
if layer.fields()[i].name() != 'stringlist2':
self.assertEqual(layer.fields()[i].type(), fields[i].type())
else:
# we automatically convert List with String subtype to StringList, to match other data providers
self.assertEqual(layer.fields()[i].type(), QVariant.StringList)
self.assertEqual(layer.fields()[i].length(), fields[i].length())
self.assertEqual(layer.fields()[i].precision(),
fields[i].precision(), fields[i].name())
# unsupported field type
fields = QgsFields()
fields.append(QgsField("rect", QVariant.RectF))
layer = QgsMemoryProviderUtils.createMemoryLayer('my name', fields)
self.assertTrue(layer.isValid())
self.assertFalse(layer.fields().isEmpty())
self.assertEqual(layer.fields()[0].name(), 'rect')
self.assertEqual(layer.fields()[0].type(),
QVariant.String) # should be mapped to string
# field precision
fields = QgsFields()
fields.append(QgsField("string", QVariant.String, len=10))
fields.append(QgsField("long", QVariant.LongLong, len=6))
fields.append(QgsField("double", QVariant.Double, len=10, prec=7))
fields.append(QgsField("double2", QVariant.Double, len=-1, prec=-1))
layer = QgsMemoryProviderUtils.createMemoryLayer('my name', fields)
self.assertTrue(layer.isValid())
self.assertFalse(layer.fields().isEmpty())
self.assertEqual(len(layer.fields()), len(fields))
for i in range(len(fields)):
self.assertEqual(layer.fields()[i].name(), fields[i].name())
self.assertEqual(layer.fields()[i].type(), fields[i].type())
self.assertEqual(layer.fields()[i].length(), fields[i].length())
self.assertEqual(layer.fields()[i].precision(),
fields[i].precision())
def testWriteReadXmlProj6(self):
# setup a context
context = QgsCoordinateTransformContext()
proj_1 = '+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +proj=push +v_3 +step +proj=cart +ellps=intl +step +proj=helmert +x=-18.944 +y=-379.364 +z=-24.063 +rx=-0.04 +ry=0.764 +rz=-6.431 +s=3.657 +convention=coordinate_frame +step +inv +proj=cart +ellps=WGS84 +step +proj=pop +v_3 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1'
proj_2 = '+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +proj=push +v_3 +step +proj=cart +ellps=intl +step +proj=helmert +x=-150 +y=-250 +z=-1 +step +inv +proj=cart +ellps=WGS84 +step +proj=pop +v_3 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1'
proj_3 = '+proj=pipeline +step +proj=axisswap +order=2,1'
self.assertTrue(
context.addCoordinateOperation(
QgsCoordinateReferenceSystem('EPSG:4204'),
QgsCoordinateReferenceSystem('EPSG:4326'), proj_1, True))
self.assertTrue(
context.addCoordinateOperation(
QgsCoordinateReferenceSystem('EPSG:4205'),
QgsCoordinateReferenceSystem('EPSG:4326'), proj_2, False))
# also insert a crs with no authid available
self.assertTrue(
context.addCoordinateOperation(
QgsCoordinateReferenceSystem.fromProj(
"+proj=longlat +a=6378137 +rf=298.25722356300003 +no_defs"
), QgsCoordinateReferenceSystem('EPSG:4326'), proj_3, False))
self.assertEqual(
context.coordinateOperations(), {
('EPSG:4204', 'EPSG:4326'): proj_1,
('EPSG:4205', 'EPSG:4326'): proj_2,
('', 'EPSG:4326'): proj_3
})
# save to xml
doc = QDomDocument("testdoc")
elem = doc.createElement("test")
context.writeXml(elem, QgsReadWriteContext())
# restore from xml
context2 = QgsCoordinateTransformContext()
context2.readXml(elem, QgsReadWriteContext())
# check result
self.assertEqual(
context2.coordinateOperations(), {
('EPSG:4204', 'EPSG:4326'): proj_1,
('EPSG:4205', 'EPSG:4326'): proj_2,
('', 'EPSG:4326'): proj_3
})
self.assertEqual(
context2.calculateCoordinateOperation(
QgsCoordinateReferenceSystem.fromProj(
"+proj=longlat +a=6378137 +rf=298.25722356300003 +no_defs"
), QgsCoordinateReferenceSystem('EPSG:4326')),
'+proj=pipeline +step +proj=axisswap +order=2,1')
self.assertFalse(
context2.mustReverseCoordinateOperation(
QgsCoordinateReferenceSystem.fromProj(
"+proj=longlat +a=6378137 +rf=298.25722356300003 +no_defs"
), QgsCoordinateReferenceSystem('EPSG:4326')))
self.assertEqual(
context2.calculateCoordinateOperation(
QgsCoordinateReferenceSystem('EPSG:4326'),
QgsCoordinateReferenceSystem.fromProj(
"+proj=longlat +a=6378137 +rf=298.25722356300003 +no_defs")
), '+proj=pipeline +step +proj=axisswap +order=2,1')
self.assertTrue(
context2.mustReverseCoordinateOperation(
QgsCoordinateReferenceSystem('EPSG:4326'),
QgsCoordinateReferenceSystem.fromProj(
"+proj=longlat +a=6378137 +rf=298.25722356300003 +no_defs")
))
self.assertTrue(
context2.allowFallbackTransform(
QgsCoordinateReferenceSystem('EPSG:4204'),
QgsCoordinateReferenceSystem('EPSG:4326')))
self.assertFalse(
context2.allowFallbackTransform(
QgsCoordinateReferenceSystem('EPSG:4205'),
QgsCoordinateReferenceSystem('EPSG:4326')))
