https://github.com/sidneycadot/oeis

Code to download, process, and analyse the Online Encyclopedia of Integer Sequences
https://github.com/sidneycadot/oeis

Last synced: 3 months ago
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Code to download, process, and analyse the Online Encyclopedia of Integer Sequences

• Host: GitHub
• URL: https://github.com/sidneycadot/oeis
• Owner: sidneycadot
• Created: 2015-09-05T06:11:24.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2023-04-01T10:23:57.000Z (almost 2 years ago)
• Last Synced: 2024-01-25T07:09:13.056Z (about 1 year ago)
• Language: Python
• Homepage:
• Size: 815 KB
• Stars: 44
• Watchers: 4
• Forks: 35
• Open Issues: 4
• Metadata Files:
  • Readme: README.md

Awesome Lists containing this project

• fucking-awesome-readme - sidneycadot/oeis - Overview. List of required dependencies. Complete list of all files in the repo and what their function is. Visual graph of how it all ties together. (Examples)
• awesome-readme - sidneycadot/oeis - Overview. List of required dependencies. Complete list of all files in the repo and what their function is. Visual graph of how it all ties together. (Examples)
• awesome-readme - sidneycadot/oeis - Overview. List of required dependencies. Complete list of all files in the repo and what their function is. Visual graph of how it all ties together. (Examples)

README

        
OEIS Tools

==========

This repository contains scripts to download, process, and analyze data from the

Online Encyclopedia of Integer Sequences (OEIS), as hosted on http://www.oeis.org.

Overview

--------

Our tools handle OEIS data from three sources:

1. remote: the OEIS database residing on the oeis.org server. The remote database can be accessed via HTTP or HTTPS requests.

2. local sqlite3: a replica of the remote database as a local SQLite3 database file.

3. local pickle: the OEIS database a a local pickle-format file, used for local analysis. The "pickle" format is Python-specific.

The local sqlite3 database is obtained from the remote database by an automatic web-crawler called 'fetch_oeis_database.py'.

It contains the sequence metadata in the internal format as it is used on the remote side, as well as so called 'b-file'

data that contain sequence data *a(n)* up to high values of *n*.

The local pickle format database is obtained from the local_sqlite3 database by parsing the data and turning it into OeisEntry

instances. The pickled list of all OeisEntry instances can be read in its entirety within a few seconds.

Apart from these sources that describe the OEIS data, we also use the "catalog", which is a Python module that contains

implementations of sequence generating functions.

Dependencies

------------

- All code is written in Python 3.

- Some code depends on the 'numpy' library:

  - show_database_time.py

  - solve_linear_sequence.py

- Some code depends on the 'matplotlib' library:

  - show_database_time.py

Description of files

--------------------

Non-Python files:

filename                          |  description

----------------------------------|------------------------------------------------------------------------------------

README.md                         |  Text file (markdown format) description of the project.

catalog_files/*.json              |  Catalog files, describing parametrized sequence generating functions.

Python scripts files:

filename                          |  description

----------------------------------|------------------------------------------------------------------------------------

fetch_oeis_database.py            |  Fetch and refresh data from the remote OEIS database to a local sqlite3 database.

show_database_time.py             |  Visualize time stamps in a given local sqlite3 OEIS database.

parse_oeis_database.py            |  Parse a local sqlite3 database and produce a local pickle database.

find_sequences.py                 |  Probe a local pickle database for a given sequence (work in progress).

pickle_to_json.py                 |  Read a local pickle database and write a JSON version.

solve_linear_sequence.py          |  Find linear sequences in a local 'pickle' database.

check_database.py                 |  Perform a number of checks on the data in a local pickle database.

verify_oeis_catalog.py            |  Verify the catalog.

Python modules:

filename                          |  description

----------------------------------|------------------------------------------------------------------------------------

fraction_based_linear_algebra.py  |  Perform matrix inversion without loss of precision using the Fraction type.

charmap.py                        |  Defines lists of acceptable characters for the OEIS directives.

OeisEntry.py                      |  Defines a simple class that contains (most of) the data of a single OEIS sequence.

timer.py                          |  Simplifies timing lengthy operations using a context manager.

fetch_remote_oeis_entry.py        |  Fetches a single sequence's data from the OEIS website (www.oeis.org).

catalog.py                        |  Access the local catalog.

How it all fits together

------------------------