Package: database-knotinfo
Database KnotInfoThis repository contains a snapshot of the complete content
of theKnotInfoandLinkInfodatabases.
Each database is provided as a Python list of Python dictionaries.
The data are from the corresponding Excel spreadsheets available
on the KnotInfo and LinkInfo homepages on the date of release.Please note that the databases contain columns that are not visible on
the web pages (see also theRelease Notes 2023.4.8).
The validity of the information in such columns cannot be guaranteed.
Also, there are plans to remove them in the future.This repository was created as a part of theSageMathinterface to these databases
(see thecorresponding sectionof the SageMath reference manual orthis tutorial)
but can also be used independently.In Python, it can be used as follows:>>>fromdatabase_knotinfoimportlink_list>>>k=link_list()>>>len(k)2979>>>names_k=k[0]>>>type(names_k)<type'dict'>>>>names_k['braid_index']'Braid Index'>>>k2=k[2]>>>k2['name']'3_1'>>>k2['braid_index']'2'>>>k2['homfly_polynomial']'(2*v^2-v^4)+(v^2)*z^2'>>>l=link_list(proper_links=True)>>>len(l)4189>>>names_l=l[0]>>>type(names_l)<type'dict'>>>>names_l['braid_notation']'Braid Notation'>>>l2=l[2]>>>l2['name']'L2a1{1}'>>>l2['homflypt_polynomial']'v/z-v^3/z + v*z'To build a new release, theCSVfiles can be upgraded with thecreate_knotinfo_csv.pyscript. Acronjobexecutes it on the first day of every month and creates a new
release if differences are detected.InstallationPythonpipinstalldatabase_knotinfoorpipinstalldatabase_knotinfo==2021.9.1if you want to install a former version.SageMathSince Release 9.4, the database can be installed in Sage by:sage-idatabase_knotinfoThis will contain integration with the knot and link functionality of Sage.
Sage 9.4 ships the PyPI release0.7of the database. To use a more recent one you have to executesage-packageupdatedatabase_knotinfo<version>before the installation command above, for example:sage-packageupdatedatabase_knotinfo2021.9.1This procedure can be used to upgrade to the next version, as well. But note
that there is a bug in 9.4 concerning such upgrades which will be fixed in
SageMath 9.5 (see Trac ticket#32099).
A workaround for 9.4 can be perfomed in a Sage session as follows:sage: from sage.databases.knotinfo_db import KnotInfoDataBase
sage: KnotInfoDataBase().reset_filecache()If you upgrade to a version of the database which is ahead of the version the
SageMath release is build on, you should keep in mind, that the examples shown
in the Sage reference manual may be outdated.In case the installation viasage -iis failing on your system you can try:sage-pipinstalldatabase_knotinfoorsage-pipinstalldatabase_knotinfo==0.7for the version compatible the the current Sage release.VersioningVersion numbers are automatically generated every month if differences to the
original databases are detected. They follow the scheme<year>.<month>.<day>HelpIf you note a divergence between this repository and the original data in case
the current release is older than a month please create an issue about that.CreditsMany thanks to Chuck Livingston and Allison Moore for making the data
available. For further acknowledgments see the corresponding homepages.