pyqtree module
API Documentation
Classes
class Index
The top spatial index to be created by the user. Once created it can be populated with geographically placed members that can later be tested for intersection with a user inputted geographic bounding box. Note that the index can be iterated through in a for-statement, which loops through all all the quad instances and lets you access their properties.
Example usage:
spindex = Index(bbox=(0, 0, 100, 100)) spindex.insert('duck', (50, 30, 53, 60)) spindex.insert('cookie', (10, 20, 15, 25)) spindex.insert('python', (40, 50, 95, 90)) results = spindex.intersect((51, 51, 86, 86)) sorted(results) ['duck', 'python']
Ancestors (in MRO)
- Index
- pyqtree._QuadTree
- __builtin__.object
Methods
def __init__(
self, bbox=None, x=None, y=None, width=None, height=None, max_items=10, max_depth=20)
Initiate by specifying either 1) a bbox to keep track of, or 2) with an xy centerpoint and a width and height.
Parameters: - bbox: The coordinate system bounding box of the area that the quadtree should keep track of, as a 4-length sequence (xmin,ymin,xmax,ymax) - x: The x center coordinate of the area that the quadtree should keep track of. - y The y center coordinate of the area that the quadtree should keep track of. - width: How far from the xcenter that the quadtree should look when keeping track. - height: How far from the ycenter that the quadtree should look when keeping track - max_items (optional): The maximum number of items allowed per quad before splitting up into four new subquads. Default is 10. - max_depth (optional): The maximum levels of nested subquads, after which no more splitting occurs and the bottommost quad nodes may grow indefinately. Default is 20.
def insert(
self, item, bbox)
Inserts an item into the quadtree along with its bounding box.
Parameters: - item: The item to insert into the index, which will be returned by the intersection method - bbox: The spatial bounding box tuple of the item, with four members (xmin,ymin,xmax,ymax)
def intersect(
self, bbox)
Intersects an input boundingbox rectangle with all of the items contained in the quadtree.
Parameters: - bbox: A spatial bounding box tuple with four members (xmin,ymin,xmax,ymax)
Returns: - A list of inserted items whose bounding boxes intersect with the input bbox.
def remove(
self, item, bbox)
Removes an item from the quadtree.
Parameters: - item: The item to remove from the index - bbox: The spatial bounding box tuple of the item, with four members (xmin,ymin,xmax,ymax)
Both parameters need to exactly match the parameters provided to the insert method.