[r-t] Lead head codes redux

[Graham John]

On 20 June 2017 at 18:30, Don Morrison <dfm at ringing.org> wrote:

> But for the single hunt at odd stages/twin hunt at even stages ones they've
> only left gaps for methods whose course length is not half the number of
> working bells. For example, while there is a '*' left for p1 at Fourteen,
> 1297E5A3B4T608, there's no slot for 127593E4A6B8T0, which means such a ends
> place methods needs to be described as something silly like p½ (or maybe
> p0.5) and a 14ths place 12E9A7B5T30486 would be r1½ or r1.5.
>
> Any idea why this unfortunate asymmetry was built into this scheme?

I don't know the answer to the history question, but came across the
issue a few weeks ago when I wrote an efficient little algorithm for
determining whether a leadhead is a plain bob leadhead and derive the
leadhead code at any stage without the need for lookup tables.

I wondered whether we might be able to renumber them to work like the
even stages. Does anyone know of any reason why doing that might be a
problem?

Graham