georaptor

GeoRaptor: Python Geohash Compression Tool

Geohash is a geocoding system invented by Gustavo Niemeyer and placed into the public domain. It is a hierarchical spatial data structure which subdivides space into buckets of grid shape, which is one of the many applications of what is known as a Z-order curve, and generally space-filling curves.

Geohash creation for a polygon at a given precision level could result in a huge set of geohashes.

GeoRaptor creates the best combination of geohashes across various levels to represent a polygon, by starting from the highest level and iterating till the optimal blend is brewed. Result accuracy remains the same as that of the starting geohash level, but data size reduces considerably for large polygons, thereby improving speed and performance.

Following is a sample of what georaptor does

.. image:: https://raw.github.com/ashwin711/georaptor/master/images/sgp_input.png :width: 480 :height: 320 .. image:: https://raw.github.com/ashwin711/georaptor/master/images/sgp_output.png :width: 480 :height: 320

Input: 1096 geohashes at precision 6 for Singapore.

Output: 414 geohashes with a mix of precision 5 and 6.

Performance

Input sample size: 18,992,425

Output: 220,375

Total execution time: 35.8013219833 seconds

Usage

$ georaptor --output --minlevel --maxlevel

Example

$ georaptor sample.csv

OR

$ georaptor sample.csv --output sample_out.csv --minlevel 3 --maxlevel 4

Installation

To install georaptor, simply: ::

$ pip install georaptor

License:

Licensed under the Apache License, Version 2.0. ::

Copyright 2024 Ashwin Nair <https://www.linkedin.com/in/ashwin-nair7>

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.