def reproject(self, prj, name=None, chunk=1000):
"""
Reprojects a layer.
*prj* is the destination :class:`Projection <geoscript.proj.Projection>`
*name* is the optional name as a ``str`` to assign to the resulting reprojected layer.
This method returns a newly reprojected layer. The new layer is create within the containing workspace of the original layer.
>>> from geoscript import geom
>>> l = Layer()
>>> l.proj = 'epsg:4326'
>>> l.add([geom.Point(-111, 45.7)])
>>>
>>> l2 = l.reproject('epsg:26912')
>>> l2.proj.id
'EPSG:26912'
>>> [f.geom.round() for f in l2.features()]
[POINT (500000 5060716)]
"""
prj = proj.Projection(prj)
name = name or Layer._newname()
# reproject the schema
rschema = self.schema.reproject(prj, name)
# create the reprojected layer
rlayer = self.workspace.create(schema=rschema)
# create a query specifying that feautres should be reprojected
q = DefaultQuery(self.name, Filter.PASS._filter)
if self.proj:
q.coordinateSystem = self.proj._crs
q.coordinateSystemReproject = prj._crs
# loop through features and add to new reprojeced layer
fit = self._source.getFeatures(q).features()
try:
while True:
features = readFeatures(fit, self._source.getSchema(), chunk)
if features.isEmpty():
break
rlayer._source.addFeatures(features)
finally:
fit.close()
return rlayer
def reproject(self, prj, name=None, chunk=1000):
"""
Reprojects a layer.
*prj* is the destination :class:`Projection <geoscript.proj.Projection>`
*name* is the optional name as a ``str`` to assign to the resulting reprojected layer.
This method returns a newly reprojected layer. The new layer is create within the containing workspace of the original layer.
>>> from geoscript import geom
>>> l = Layer()
>>> l.proj = 'epsg:4326'
>>> l.add([geom.Point(-111, 45.7)])
>>>
>>> l2 = l.reproject('epsg:26912')
>>> l2.proj.id
'EPSG:26912'
>>> [f.geom.round() for f in l2.features()]
[POINT (500000 5060716)]
"""
prj = proj.Projection(prj)
name = name or Layer._newname()
# reproject the schema
rschema = self.schema.reproject(prj, name)
# create the reprojected layer
rlayer = self.workspace.create(schema=rschema)
# create a query specifying that feautres should be reprojected
q = DefaultQuery(self.name, Filter.PASS._filter)
if self.proj:
q.coordinateSystem = self.proj._crs
q.coordinateSystemReproject = prj._crs
# loop through features and add to new reprojeced layer
fit = self._source.getFeatures(q).features()
try:
while True:
features = readFeatures(fit, self._source.getSchema(), chunk)
if features.isEmpty():
break
rlayer._source.addFeatures(features)
finally:
fit.close()
return rlayer
def add(self, layer, name=None, chunk=1000):
"""
Adds an existing layer to the workspace.
*layer* is the :class:`Layer <geoscript.layer.layer.Layer>` to add.
*name* is the optional name as a ``str`` to assign to the layer when copied into the workspace.
>>> ws = Workspace()
>>> ws.layers()
[]
>>> from geoscript.layer import Layer
>>> l = Layer('foo')
>>> l = ws.add(l)
>>> ws.layers()
['foo']
"""
name = name if name else layer.name
try:
self.get(name)
raise Exception('Layer named "%s" already exists.' % name)
except KeyError:
if layer.proj:
flds = []
for fld in layer.schema.fields:
flds.append((fld.name, fld.typ, layer.proj
) if issubclass(fld.typ, geom.Geometry) else (
fld.name, fld.typ))
else:
flds = [(fld.name, fld.typ) for fld in layer.schema.fields]
l = self.create(name, flds)
# add all the features
it = layer._source.getFeatures().features()
try:
while True:
features = readFeatures(it, layer._source.getSchema(),
chunk)
if features.isEmpty():
break
l._source.addFeatures(features)
return l
finally:
it.close()
def add(self, layer, name=None, chunk=1000):
"""
Adds an existing layer to the workspace.
*layer* is the :class:`Layer <geoscript.layer.layer.Layer>` to add.
*name* is the optional name as a ``str`` to assign to the layer when copied into the workspace.
>>> ws = Workspace()
>>> ws.layers()
[]
>>> from geoscript.layer import Layer
>>> l = Layer('foo')
>>> l = ws.add(l)
>>> ws.layers()
['foo']
"""
name = name if name else layer.name
try:
self.get(name)
raise Exception('Layer named "%s" already exists.' % name)
except KeyError:
if layer.proj:
flds = []
for fld in layer.schema.fields:
flds.append(
(fld.name, fld.typ, layer.proj) if issubclass(fld.typ, geom.Geometry) else (fld.name, fld.typ)
)
else:
flds = [(fld.name, fld.typ) for fld in layer.schema.fields]
l = self.create(name, flds)
# add all the features
it = layer._source.getFeatures().features()
try:
while True:
features = readFeatures(it, layer._source.getSchema(), chunk)
if features.isEmpty():
break
l._source.addFeatures(features)
return l
finally:
it.close()
