def next(self):
"""::
>>> mun = Vector('boundary_municp_sqlite')
>>> mun.open()
>>> mun.next()
Boundary(v_id=None)
>>> mun.next()
Boundary(v_id=None)
>>> mun.close()
..
"""
v_id = self.c_mapinfo.contents.next_line
v_id = v_id if v_id != 0 else None
c_points = ctypes.pointer(libvect.line_pnts())
c_cats = ctypes.pointer(libvect.line_cats())
ftype = libvect.Vect_read_next_line(self.c_mapinfo, c_points, c_cats)
if ftype == -2:
raise StopIteration()
if ftype == -1:
raise
#if GV_TYPE[ftype]['obj'] is not None:
return GV_TYPE[ftype]['obj'](v_id=v_id,
c_mapinfo=self.c_mapinfo,
c_points=c_points,
c_cats=c_cats)
def __init__(self, c_mapinfo, v_id, c_cats=None):
self.c_mapinfo = c_mapinfo
self.id = v_id
if c_cats is not None:
self.c_cats = c_cats
else:
self.c_cats = ctypes.pointer(libvect.line_cats())
self.get_area_cats()
def __init__(self, v_id=None, c_mapinfo=None, c_points=None, c_cats=None):
self.id = v_id # vector id
self.c_mapinfo = c_mapinfo
# set c_points
if c_points is None:
self.c_points = ctypes.pointer(libvect.line_pnts())
else:
self.c_points = c_points
# set c_cats
if c_cats is None:
self.c_cats = ctypes.pointer(libvect.line_cats())
else:
self.c_cats = c_cats
def read(self, feature_id):
"""Return a geometry object given the feature id. ::
>>> mun = VectTopo('boundary_municp_sqlite')
>>> mun.open()
>>> feature1 = mun.read(0) #doctest: +ELLIPSIS
Traceback (most recent call last):
...
ValueError: The index must be >0, 0 given.
>>> feature1 = mun.read(1)
>>> feature1
Boundary(v_id=1)
>>> feature1.length()
1415.3348048582038
>>> mun.read(-1)
Centoid(649102.382010, 15945.714502)
>>> len(mun)
8707
>>> mun.read(8707)
Centoid(649102.382010, 15945.714502)
>>> mun.read(8708) #doctest: +ELLIPSIS
Traceback (most recent call last):
...
IndexError: Index out of range
>>> mun.close()
..
"""
if feature_id < 0: # Handle negative indices
feature_id += self.__len__() + 1
if feature_id >= (self.__len__() + 1):
raise IndexError('Index out of range')
if feature_id > 0:
c_points = ctypes.pointer(libvect.line_pnts())
c_cats = ctypes.pointer(libvect.line_cats())
ftype = libvect.Vect_read_line(self.c_mapinfo, c_points, c_cats,
feature_id)
if GV_TYPE[ftype]['obj'] is not None:
return GV_TYPE[ftype]['obj'](v_id=feature_id,
c_mapinfo=self.c_mapinfo,
c_points=c_points,
c_cats=c_cats)
else:
raise ValueError('The index must be >0, %r given.' % feature_id)
def __init__(self, c_cats=None):
self.c_cats = c_cats if c_cats else ctypes.pointer(libvect.line_cats())
def areas_to_wkb_list(self, bbox=None, field=1):
"""Return all features of type point, line, boundary or centroid
as a list of Well Known Binary representations (WKB)
(id, cat, wkb) triplets located in a specific
bounding box.
:param bbox: The boundingbox to search for features,
if bbox=None the boundingbox of the whole
vector map layer is used
:type bbox: grass.pygrass.vector.basic.Bbox
:param field: The centroid category field
:type field: integer
:return: A list of triplets, or None if nothing was found
The well known binary are stored in byte arrays.
Examples:
>>> from grass.pygrass.vector import VectorTopo
>>> from grass.pygrass.vector.basic import Bbox
>>> test_vect = VectorTopo(test_vector_name)
>>> test_vect.open('r')
>>> bbox = Bbox(north=20, south=-1, east=20, west=-1)
>>> result = test_vect.areas_to_wkb_list(bbox=bbox)
>>> len(result)
4
>>> for entry in result:
... a_id, cat, wkb = entry
... print((a_id, cat, len(wkb)))
(1, 3, 225)
(2, 3, 141)
(3, 3, 93)
(4, 3, 141)
>>> result = test_vect.areas_to_wkb_list()
>>> len(result)
4
>>> for entry in result:
... a_id, cat, wkb = entry
... print((a_id, cat, len(wkb)))
(1, 3, 225)
(2, 3, 141)
(3, 3, 93)
(4, 3, 141)
>>> test_vect.close()
"""
if bbox is None:
bbox = self.bbox()
bboxlist = self.find_by_bbox.areas(bbox, bboxlist_only = True)
if bboxlist is not None and len(bboxlist) > 0:
l = []
line_c = libvect.line_cats()
size = ctypes.c_size_t()
cat = ctypes.c_int()
for a_id in bboxlist.ids:
barray = libvect.Vect_read_area_to_wkb(self.c_mapinfo,
a_id,
ctypes.byref(size))
if not barray:
raise GrassError(_("Unable to read area with id %i"%(a_id)))
pcat = None
c_ok = libvect.Vect_get_area_cats(self.c_mapinfo, a_id,
ctypes.byref(line_c))
if c_ok == 0: # Centroid found
ok = libvect.Vect_cat_get(ctypes.byref(line_c), field,
ctypes.byref(cat))
if ok > 0:
pcat = cat.value
l.append((a_id, pcat, ctypes.string_at(barray, size.value)))
libgis.G_free(barray)
return l
return None
def features_to_wkb_list(self, bbox=None, feature_type="point", field=1):
"""Return all features of type point, line, boundary or centroid
as a list of Well Known Binary representations (WKB)
(id, cat, wkb) triplets located in a specific
bounding box.
:param bbox: The boundingbox to search for features,
if bbox=None the boundingbox of the whole
vector map layer is used
:type bbox: grass.pygrass.vector.basic.Bbox
:param feature_type: The type of feature that should be converted to
the Well Known Binary (WKB) format. Supported are:
'point' -> libvect.GV_POINT 1
'line' -> libvect.GV_LINE 2
'boundary' -> libvect.GV_BOUNDARY 3
'centroid' -> libvect.GV_CENTROID 4
:type type: string
:param field: The category field
:type field: integer
:return: A list of triplets, or None if nothing was found
The well known binary are stored in byte arrays.
Examples:
>>> from grass.pygrass.vector import VectorTopo
>>> from grass.pygrass.vector.basic import Bbox
>>> test_vect = VectorTopo(test_vector_name)
>>> test_vect.open('r')
>>> bbox = Bbox(north=20, south=-1, east=20, west=-1)
>>> result = test_vect.features_to_wkb_list(bbox=bbox,
... feature_type="point")
>>> len(result)
3
>>> for entry in result:
... f_id, cat, wkb = entry
... print((f_id, cat, len(wkb)))
(1, 1, 21)
(2, 1, 21)
(3, 1, 21)
>>> result = test_vect.features_to_wkb_list(bbox=None,
... feature_type="line")
>>> len(result)
3
>>> for entry in result:
... f_id, cat, wkb = entry
... print((f_id, cat, len(wkb)))
(4, 2, 57)
(5, 2, 57)
(6, 2, 57)
>>> result = test_vect.features_to_wkb_list(bbox=bbox,
... feature_type="boundary")
>>> len(result)
11
>>> result = test_vect.features_to_wkb_list(bbox=None,
... feature_type="centroid")
>>> len(result)
4
>>> for entry in result:
... f_id, cat, wkb = entry
... print((f_id, cat, len(wkb)))
(19, 3, 21)
(18, 3, 21)
(20, 3, 21)
(21, 3, 21)
>>> result = test_vect.features_to_wkb_list(bbox=bbox,
... feature_type="blub")
Traceback (most recent call last):
...
GrassError: Unsupported feature type <blub>, supported are <point,line,boundary,centroid>
>>> test_vect.close()
"""
supported = ['point', 'line', 'boundary', 'centroid']
if feature_type.lower() not in supported:
raise GrassError("Unsupported feature type <%s>, "\
"supported are <%s>"%(feature_type,
",".join(supported)))
if bbox is None:
bbox = self.bbox()
bboxlist = self.find_by_bbox.geos(bbox, type=feature_type.lower(),
bboxlist_only = True)
if bboxlist is not None and len(bboxlist) > 0:
l = []
line_p = libvect.line_pnts()
line_c = libvect.line_cats()
size = ctypes.c_size_t()
cat = ctypes.c_int()
error = ctypes.c_int()
for f_id in bboxlist.ids:
barray = libvect.Vect_read_line_to_wkb(self.c_mapinfo,
ctypes.byref(line_p),
ctypes.byref(line_c),
f_id,
ctypes.byref(size),
ctypes.byref(error))
if not barray:
if error == -1:
raise GrassError(_("Unable to read line of feature %i"%(f_id)))
if error == -2:
print("Empty feature %i"%(f_id))
continue
ok = libvect.Vect_cat_get(ctypes.byref(line_c), field,
ctypes.byref(cat))
if ok < 1:
pcat = None
else:
pcat = cat.value
l.append((f_id, pcat, ctypes.string_at(barray, size.value)))
libgis.G_free(barray)
return l
return None
def areas_to_wkb_list(self, bbox=None, field=1):
"""Return all features of type point, line, boundary or centroid
as a list of Well Known Binary representations (WKB)
(id, cat, wkb) triplets located in a specific
bounding box.
:param bbox: The boundingbox to search for features,
if bbox=None the boundingbox of the whole
vector map layer is used
:type bbox: grass.pygrass.vector.basic.Bbox
:param field: The centroid category field
:type field: integer
:return: A list of triplets, or None if nothing was found
The well known binary are stored in byte arrays.
Examples:
>>> from grass.pygrass.vector import VectorTopo
>>> from grass.pygrass.vector.basic import Bbox
>>> test_vect = VectorTopo(test_vector_name)
>>> test_vect.open('r')
>>> bbox = Bbox(north=20, south=-1, east=20, west=-1)
>>> result = test_vect.areas_to_wkb_list(bbox=bbox)
>>> len(result)
4
>>> for entry in result:
... a_id, cat, wkb = entry
... print((a_id, cat, len(wkb)))
(1, 3, 225)
(2, 3, 141)
(3, 3, 93)
(4, 3, 141)
>>> result = test_vect.areas_to_wkb_list()
>>> len(result)
4
>>> for entry in result:
... a_id, cat, wkb = entry
... print((a_id, cat, len(wkb)))
(1, 3, 225)
(2, 3, 141)
(3, 3, 93)
(4, 3, 141)
>>> test_vect.close()
"""
if bbox is None:
bbox = self.bbox()
bboxlist = self.find_by_bbox.areas(bbox, bboxlist_only = True)
if bboxlist is not None and len(bboxlist) > 0:
l = []
line_c = libvect.line_cats()
size = ctypes.c_size_t()
cat = ctypes.c_int()
for a_id in bboxlist.ids:
barray = libvect.Vect_read_area_to_wkb(self.c_mapinfo,
a_id,
ctypes.byref(size))
if not barray:
raise GrassError(_("Unable to read area with id %i"%(a_id)))
pcat = None
c_ok = libvect.Vect_get_area_cats(self.c_mapinfo, a_id,
ctypes.byref(line_c))
if c_ok == 0: # Centroid found
ok = libvect.Vect_cat_get(ctypes.byref(line_c), field,
ctypes.byref(cat))
if ok > 0:
pcat = cat.value
l.append((a_id, pcat, ctypes.string_at(barray, size.value)))
libgis.G_free(barray)
return l
return None
def features_to_wkb_list(self, bbox=None, feature_type="point", field=1):
"""Return all features of type point, line, boundary or centroid
as a list of Well Known Binary representations (WKB)
(id, cat, wkb) triplets located in a specific
bounding box.
:param bbox: The boundingbox to search for features,
if bbox=None the boundingbox of the whole
vector map layer is used
:type bbox: grass.pygrass.vector.basic.Bbox
:param feature_type: The type of feature that should be converted to
the Well Known Binary (WKB) format. Supported are:
'point' -> libvect.GV_POINT 1
'line' -> libvect.GV_LINE 2
'boundary' -> libvect.GV_BOUNDARY 3
'centroid' -> libvect.GV_CENTROID 4
:type type: string
:param field: The category field
:type field: integer
:return: A list of triplets, or None if nothing was found
The well known binary are stored in byte arrays.
Examples:
>>> from grass.pygrass.vector import VectorTopo
>>> from grass.pygrass.vector.basic import Bbox
>>> test_vect = VectorTopo(test_vector_name)
>>> test_vect.open('r')
>>> bbox = Bbox(north=20, south=-1, east=20, west=-1)
>>> result = test_vect.features_to_wkb_list(bbox=bbox,
... feature_type="point")
>>> len(result)
3
>>> for entry in result:
... f_id, cat, wkb = entry
... print((f_id, cat, len(wkb)))
(1, 1, 21)
(2, 1, 21)
(3, 1, 21)
>>> result = test_vect.features_to_wkb_list(bbox=None,
... feature_type="line")
>>> len(result)
3
>>> for entry in result:
... f_id, cat, wkb = entry
... print((f_id, cat, len(wkb)))
(4, 2, 57)
(5, 2, 57)
(6, 2, 57)
>>> result = test_vect.features_to_wkb_list(bbox=bbox,
... feature_type="boundary")
>>> len(result)
11
>>> result = test_vect.features_to_wkb_list(bbox=None,
... feature_type="centroid")
>>> len(result)
4
>>> for entry in result:
... f_id, cat, wkb = entry
... print((f_id, cat, len(wkb)))
(19, 3, 21)
(18, 3, 21)
(20, 3, 21)
(21, 3, 21)
>>> result = test_vect.features_to_wkb_list(bbox=bbox,
... feature_type="blub")
Traceback (most recent call last):
...
GrassError: Unsupported feature type <blub>, supported are <point,line,boundary,centroid>
>>> test_vect.close()
"""
supported = ['point', 'line', 'boundary', 'centroid']
if feature_type.lower() not in supported:
raise GrassError("Unsupported feature type <%s>, "\
"supported are <%s>"%(feature_type,
",".join(supported)))
if bbox is None:
bbox = self.bbox()
bboxlist = self.find_by_bbox.geos(bbox, type=feature_type.lower(),
bboxlist_only = True)
if bboxlist is not None and len(bboxlist) > 0:
l = []
line_p = libvect.line_pnts()
line_c = libvect.line_cats()
size = ctypes.c_size_t()
cat = ctypes.c_int()
error = ctypes.c_int()
for f_id in bboxlist.ids:
barray = libvect.Vect_read_line_to_wkb(self.c_mapinfo,
ctypes.byref(line_p),
ctypes.byref(line_c),
f_id,
ctypes.byref(size),
ctypes.byref(error))
if not barray:
if error == -1:
raise GrassError(_("Unable to read line of feature %i"%(f_id)))
if error == -2:
print("Empty feature %i"%(f_id))
continue
ok = libvect.Vect_cat_get(ctypes.byref(line_c), field,
ctypes.byref(cat))
if ok < 1:
pcat = None
else:
pcat = cat.value
l.append((f_id, pcat, ctypes.string_at(barray, size.value)))
libgis.G_free(barray)
return l
return None
def __init__(self, c_cats=None):
self.c_cats = c_cats if c_cats else ctypes.pointer(libvect.line_cats())
