This is one of several challenges left for the community by Calvin's Hobbies. The curve that an idealised hanging rope or chain makes is a catenary. Image by Bin im Garten, via Wikimedia Commons.
Stephen Wallis
I Cover the Waterfront Select Non-fiction Articles of Bob Frump
[Vex] Catenary passing through 2 points – Foggyhazel
These files were assembled by L. John Old, Napier - Cd3wd.com
Scientific Sprague, by Francis Lynde—A Project Gutenberg eBook
Common OMMON
code challenge - Travelling Salesman - Code Golf Stack Exchange
United States Coast Pilot by United States Office of Coast Survey
リース契約可能】GAUSIUM(ガウシウム)チャージングステーション