Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site ames.UUCP Path: utzoo!watmath!clyde!bonnie!akgua!sdcsvax!sdcrdcf!hplabs!hao!ames!jaw From: jaw@ames.UUCP (James A. Woods) Newsgroups: net.followup Subject: Re: Permutation Algorithms and Change Ringing Message-ID: <736@ames.UUCP> Date: Fri, 28-Dec-84 23:21:35 EST Article-I.D.: ames.736 Posted: Fri Dec 28 23:21:35 1984 Date-Received: Sun, 30-Dec-84 01:59:54 EST References: <195@cheviot.UUCP> Organization: NASA-Ames Research Center, Mtn. View, CA Lines: 48 # Note: The following tintinnalogical offering should be read whilst humming # Pete Seeger's "The Bells of Rhymney" (1964) in the key of control-G. We laud our very own campanologist Robert Stroud (ukc!cheviot!robert) for his commentary on change-ringing. His account certainly rings true; I only wish to add a reference to the lore, to be found in the December 1977 issue of ACM Computing Surveys. In his fascinating addendum to Robert Sedgewick's classic exposition "Permutation generation methods" (appearing in the same journal, June 1977), a Mr. I. R. MacCallum of the Dept. of Computer Science, Univ. of Essex at Colchester, chimes in to discuss the following bits of ephemera: (a) the roots of the Johnson/Trotter algorithm (1962) in the early years of the 17th century, as reported in the collaborative effort of Stedman/Duckworth in 1688 ("Tintinnalogia", also avail. as a Kingsmead Reprint, Bath, 1970). (b) the complex definition of "peals" and "extents" provided by the Central Council of Church Bell Ringers, with applicability to the playing of Grandsire Triples, a particularly harmonious composition of 5,040 (7!) changes. MacCallum, incidently, offers Algol 60 code for a Grandsire peal composed by John Vicars of Oxford to the interested reader. (c) accounts of 8-bell extents (40,320 changes), the only "true" performance (i.e. verified by independent umpires) being achieved by the Leicester Diocesan Guild at the Bell Foundry, Loughborough on Saturday July 27th, 1963, in 17 hours 58 1/2 minutes. Ah, the stuff of Guinness Book! I consider it right up there with Sedgewick's three-instruction permutation generator inner loop. Since campanologists may not resort to "visible aids to memory in conducting or ringing", the fine (read "appealing") art practiced by Mr. Stroud is algorithmic, indeed. -- James A. Woods {hplabs,ihnp4,vortex}!ames!jaw (jaw@riacs.ARPA) P.S. This writer, also, is eagerly awaiting the Macintosh multi-voice rendering of Plain Bob Major for his "wallpaper music" collection. Perhaps bessel(3M) functions would serve as the appropriate inharmonic sound envelope, with menu bars for Tibetan, Big Ben, and Liberty bell variants. Next stop -- a Phillip Glass machine! P.P.S. I hope net.audio and net.music.folk are listening in on this...