[r-t] Terminology question

[Andrew Johnson]

> From: Joe Norton 
> I may be about to ask a stupid question or two, but please humour me...
> 
> Given some block, A. A is some method or block or other ordered set 
> of changes on a given number of bells. It could be anything.
> 
> If we reflect A about its midpoint (front to back) then the block 
> produced is called "Reverse A". I think I'm still on firm ground.
> 
> First question:
> If we make "Backwards A", as in last change first and first change 
> last etc, what is that called as an operation? I'm assuming it's not
> called reversal, since that is the process of producing "Reverse A" as 
above.
> 
> Second question:
> In terms of naming, should A and "Backwards A" be related in any 
> way? This does not usually become an issue seeing as the vast 
> majority of common methods are palindromic. Methods like Polebrook 
> Bob Doubles (5.1.5.3.125.3.125.1.5.125) and Cotterstock Bob Doubles 
> (5.1.125.3.125.3.5.1.5.125) would suggest not but I wondered if 
> there have been any naming rules since then.
> 
> Thank you and sorry for asking daft questions!
> 
> Joe._____
See Martin Bright's paper about symmetries:
http://www.boojum.org.uk/ringing/symmetry.pdf
using 'vertical reflection' and
https://cccbr.github.io/method_ringing_framework/classification.html#methodsymmetry
using 'read backwards'.

Sometimes 'reverse' is used to mean going backwards, but perhaps for 
compositions where it is clear that the method is staying the same, 
but the order of the calls is reversed.

Perhaps 'retrograde' could also be considered as a term.

Andrew Johnson







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