Geospatial Indexing Example

This example shows how to create and use a GEO2D index in PyMongo.

Note

2D indexes require server version >= 1.3.4. Support for 2D indexes also requires PyMongo version >= 1.5.1.

See general MongoDB documentation

geo

Creating a Geospatial Index

Creating a geospatial index in pymongo is easy:

>>> from pymongo import Connection, GEO2D
>>> db = Connection().geo_example
>>> db.places.create_index([("loc", GEO2D)])
u'loc_2d'

Inserting Places

Locations in MongoDB are represented using either embedded documents or lists where the first two elements are coordinates. Here, we’ll insert a couple of example locations:

>>> db.places.insert({"loc": [2, 5]})
ObjectId('...')
>>> db.places.insert({"loc": [30, 5]})
ObjectId('...')
>>> db.places.insert({"loc": [1, 2]})
ObjectId('...')
>>> db.places.insert({"loc": [4, 4]})
ObjectId('...')

Querying

Using the geospatial index we can find documents near another point:

>>> for doc in db.places.find({"loc": {"$near": [3, 6]}}).limit(3):
...   repr(doc)
...
"{u'loc': [2, 5], u'_id': ObjectId('...')}"
"{u'loc': [4, 4], u'_id': ObjectId('...')}"
"{u'loc': [1, 2], u'_id': ObjectId('...')}"

It’s also possible to query for all items within a given rectangle (specified by lower-left and upper-right coordinates):

>>> for doc in db.places.find({"loc": {"$within": {"$box": [[2, 2], [5, 6]]}}}):
...   repr(doc)
...
"{u'loc': [4, 4], u'_id': ObjectId('...')}"
"{u'loc': [2, 5], u'_id': ObjectId('...')}"

Or circle (specified by center point and radius):

>>> for doc in db.places.find({"loc": {"$within": {"$center": [[0, 0], 6]}}}):
...   repr(doc)
...
"{u'loc': [1, 2], u'_id': ObjectId('...')}"
"{u'loc': [2, 5], u'_id': ObjectId('...')}"
"{u'loc': [4, 4], u'_id': ObjectId('...')}"

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