This is a program for manipulating and identifying knots and links. The primary input method for diagrams is a kind of paint program with a special paintbrush that helps with drawing crossings. You can also drag-and-drop images into the program, say a picture of a pencil, chalk, or whiteboard drawing. Try it out at https://kmill.github.io/knotfolio/
The wiki has a description of the functionality of the program.
- Knotilus
- Josh Horowitz's knot identification tool
- KLO
- The PLink editor in SnapPy
See CompuTop.org for Nathan Dunfield's list of software for computational low-dimensional topology.
Thanks to ICERM for hosting the Perspectives on Dehn Surgery summer school, where Stefan Mihajlović asked whether there existed any programs for importing knot diagrams from papers, and where Ken Baker and Nathan Dunfield were helpful while I worked on the first prototype.
Some UI ideas came from KLO and Josh Horowitz's knot identification tool.
Knot identification uses the invaluable KnotInfo and LinkInfo databases:
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C. Livingston and A. H. Moore, KnotInfo: Table of Knot Invariants, https://knotinfo.math.indiana.edu, April 17, 2021.
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C. Livingston and A. H. Moore, LinkInfo: Table of Link Invariants, https://linkinfo.sitehost.iu.edu, April 17, 2021.
The program was written with support of the Simons Foundation and NSF RTG grant DMS-1344991.
Note: This is out of date. The most recent release uses rollup, and npx rollup --config creates bundle.js.
The knotinfo module is very large, which causes the JavaScript bundler to eat an extremely large amount of memory. This requires the use of an option for node to allow more memory when running parcel:
NODE_OPTIONS=--max_old_space_size=4096 parcel index.html
A "production" bundle can be created in the dist folder with
NODE_OPTIONS=--max_old_space_size=4096 parcel build index.html --public-url ./
The command npm test runs some tests.
Comments, suggestions, bug reports, feedback, or favorite knots are welcome. You can reach me at kmill@berkeley.edu or submit a GitHub issue.
KnotFolio, Copyright (C) 2019 Kyle Miller
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
