Functions
def	vector_db
	Return the database connection details for a vector map (interface to `v.db.connect -g'). More...

def	vector_layer_db
	Return the database connection details for a vector map layer. More...

def	vector_columns
	Return a dictionary (or a list) of the columns for the database table connected to a vector map (interface to `v.info -c'). More...

def	vector_history
	Set the command history for a vector map to the command used to invoke the script (interface to `v.support'). More...

def	vector_info_topo
	Return information about a vector map (interface to `v.info -t'). More...

def	vector_db_select
	Get attribute data of selected vector map layer. More...

def	vector_what
	Query vector map at given locations. More...

Function Documentation

def python.vector.vector_columns	(	map,
		layer = `None`,
		getDict = `True`,
		args
	)

Return a dictionary (or a list) of the columns for the database table connected to a vector map (interface to `v.info -c').

 >>> vector_columns(urbanarea, getDict = True)
 {'UA_TYPE': {'index': 4, 'type': 'CHARACTER'}, 'UA': {'index': 2, 'type': 'CHARACTER'}, 'NAME': {'index': 3, 'type': 'CHARACTER'}, 'OBJECTID': {'index': 1, 'type': 'INTEGER'}, 'cat': {'index': 0, 'type': 'INTEGER'}}
 
 >>> vector_columns(urbanarea, getDict = False)
 ['cat', 'OBJECTID', 'UA', 'NAME', 'UA_TYPE']

Parameters

map	map name
layer	layer number or name (None for all layers)
getDict	True to return dictionary of columns otherwise list of column names is returned
args	(v.info's arguments)

Returns: dictionary/list of columns

Definition at line 98 of file vector.py.

References python.core.read_command().

def python.vector.vector_db	(	map,
		args
	)

Return the database connection details for a vector map (interface to `v.db.connect -g').

Example:

 >>> grass.vector_db('lakes')
 {1: {'layer': '1', 'name': '',
 'database': '/home/martin/grassdata/nc_spm_08/PERMANENT/dbf/',
 'driver': 'dbf', 'key': 'cat', 'table': 'lakes'}}

Parameters

map	vector map
args

Returns: dictionary { layer : { 'layer', 'table, 'database', 'driver', 'key' }

Definition at line 38 of file vector.py.

References python.core.read_command(), and utils.split().

Referenced by python.vector.vector_db_select(), and python.vector.vector_layer_db().

def python.vector.vector_db_select	(	map,
		layer = `1`,
		kwargs
	)

Get attribute data of selected vector map layer.

Function returns list of columns and dictionary of values ordered by key column value. Example:

 >>> print grass.vector_db_select('lakes')['columns']
 ['cat', 'AREA', 'PERIMETER', 'FULL_HYDRO', 'FULL_HYDR2', 'FTYPE', 'FCODE', 'NAME']
 >>> print grass.vector_db_select('lakes')['values'][3]
 ['3', '19512.86146', '708.44683', '4', '55652', 'LAKE/POND', '39000', '']
 >>> print grass.vector_db_select('lakes', columns = 'FTYPE')['values'][3]
 ['LAKE/POND']

Parameters

map	map name
layer	layer number
kwargs	v.db.select options

Returns: dictionary ('columns' and 'values')

Definition at line 173 of file vector.py.

References python.core.read_command(), utils.split(), and python.vector.vector_db().

def python.vector.vector_history ( map )

Set the command history for a vector map to the command used to invoke the script (interface to `v.support').

Parameters

map mapname

Returns: v.support output

Definition at line 137 of file vector.py.

References python.core.run_command().

def python.vector.vector_info_topo ( map )

Return information about a vector map (interface to `v.info -t').

Example:

 >>> grass.vector_info_topo('lakes')
 {'kernels': 0, 'lines': 0, 'centroids': 15279,
 'boundaries': 27764, 'points': 0, 'faces': 0,
 'primitives': 43043, 'islands': 7470, 'nodes': 35234, 'map3d': 0, 'areas': 15279}

Parameters

map map name

Returns: parsed output

Definition at line 149 of file vector.py.

References python.core.parse_key_val(), and python.core.read_command().

def python.vector.vector_layer_db	(	map,
		layer
	)

Return the database connection details for a vector map layer.

If db connection for given layer is not defined, fatal() is called.

Parameters

map	map name
layer	layer number

Returns: parsed output

Definition at line 80 of file vector.py.

References python.core.fatal(), and python.vector.vector_db().

def python.vector.vector_what	(	map,
		coord,
		distance = `0.0`
	)

Query vector map at given locations.

To query one vector map at one location

 print grass.vector_what(map = 'archsites', coord = (595743, 4925281), distance = 250)
 
 [{'Category': 8, 'Map': 'archsites', 'Layer': 1, 'Key_column': 'cat',
   'Database': '/home/martin/grassdata/spearfish60/PERMANENT/dbf/',
   'Mapset': 'PERMANENT', 'Driver': 'dbf',
   'Attributes': {'str1': 'No_Name', 'cat': '8'},
   'Table': 'archsites', 'Type': 'Point', 'Id': 8}]

To query one vector map with multiple layers (no additional parameters required)

 for q in grass.vector_what(map = 'some_map', coord = (596532.357143,4920486.21429), distance = 100.0):
     print q['Map'], q['Layer'], q['Attributes']
 
 new_bug_sites 1 {'str1': 'Beetle_site', 'GRASSRGB': '', 'cat': '80'}
 new_bug_sites 2 {'cat': '80'}

To query more vector maps at one location

 for q in grass.vector_what(map = ('archsites', 'roads'), coord = (595743, 4925281),
                            distance = 250):
     print q['Map'], q['Attributes']
                         
 archsites {'str1': 'No_Name', 'cat': '8'}
 roads {'label': 'interstate', 'cat': '1'}

To query one vector map at more locations

 for q in grass.vector_what(map = 'archsites', coord = [(595743, 4925281), (597950, 4918898)],
                            distance = 250):
     print q['Map'], q['Attributes']
 
 archsites {'str1': 'No_Name', 'cat': '8'}
 archsites {'str1': 'Bob_Miller', 'cat': '22'}

Parameters

map	vector map(s) to query given as string or list/tuple
coord	coordinates of query given as tuple (easting, northing) or list of tuples
distance	query threshold distance (in map units)

Returns: parsed list

Definition at line 232 of file vector.py.

References python.core.read_command(), and dialogs.type.

Functions

Function Documentation