libpysal.cg.Grid

class libpysal.cg.Grid(bounds, resolution)

Representation of a binning data structure.

__init__(bounds, resolution)

Returns a grid with specified properties.

__init__(Rectangle, number) -> Grid

Parameters:

boundsthe area for the grid to encompass

resolutionthe diameter of each bin

Examples

TODO: complete this doctest >>> g = Grid(Rectangle(0, 0, 10, 10), 1)

Methods

__init__(bounds, resolution)	Returns a grid with specified properties.
add(item, pt)	Adds an item to the grid at a specified location.
bounds(bounds)	Returns a list of items found in the grid within the bounds specified.
in_grid(loc)	Returns whether a 2-tuple location _loc_ lies inside the grid bounds.
nearest(pt)	Returns the nearest item to a point.
proximity(pt, r)	Returns a list of items found in the grid within a specified distance of a point.
remove(item, pt)	Removes an item from the grid at a specified location.

add(item, pt)

Adds an item to the grid at a specified location.

add(x, Point) -> x

Parameters:

itemthe item to insert into the grid

ptthe location to insert the item at

Examples

>>> g = Grid(Rectangle(0, 0, 10, 10), 1)
>>> g.add('A', Point((4.2, 8.7)))
'A'

bounds(bounds)

Returns a list of items found in the grid within the bounds specified.

bounds(Rectangle) -> x list

Parameters:

itemthe item to remove from the grid

ptthe location the item was added at

Examples

>>> g = Grid(Rectangle(0, 0, 10, 10), 1)
>>> g.add('A', Point((1.0, 1.0)))
'A'
>>> g.add('B', Point((4.0, 4.0)))
'B'
>>> g.bounds(Rectangle(0, 0, 3, 3))
['A']
>>> g.bounds(Rectangle(2, 2, 5, 5))
['B']
>>> sorted(g.bounds(Rectangle(0, 0, 5, 5)))
['A', 'B']

in_grid(loc)

Returns whether a 2-tuple location _loc_ lies inside the grid bounds.

Test tag: <tc>#is#Grid.in_grid</tc>

nearest(pt)

Returns the nearest item to a point.

nearest(Point) -> x

Parameters:

ptthe location to search near

Examples

>>> g = Grid(Rectangle(0, 0, 10, 10), 1)
>>> g.add('A', Point((1.0, 1.0)))
'A'
>>> g.add('B', Point((4.0, 4.0)))
'B'
>>> g.nearest(Point((2.0, 1.0)))
'A'
>>> g.nearest(Point((7.0, 5.0)))
'B'

proximity(pt, r)

Returns a list of items found in the grid within a specified distance of a point.

proximity(Point, number) -> x list

Parameters:

ptthe location to search around

rthe distance to search around the point

Examples

>>> g = Grid(Rectangle(0, 0, 10, 10), 1)
>>> g.add('A', Point((1.0, 1.0)))
'A'
>>> g.add('B', Point((4.0, 4.0)))
'B'
>>> g.proximity(Point((2.0, 1.0)), 2)
['A']
>>> g.proximity(Point((6.0, 5.0)), 3.0)
['B']
>>> sorted(g.proximity(Point((4.0, 1.0)), 4.0))
['A', 'B']

remove(item, pt)

Removes an item from the grid at a specified location.

remove(x, Point) -> x

Parameters:

itemthe item to remove from the grid

ptthe location the item was added at

Examples

>>> g = Grid(Rectangle(0, 0, 10, 10), 1)
>>> g.add('A', Point((4.2, 8.7)))
'A'
>>> g.remove('A', Point((4.2, 8.7)))
'A'