Talk:Optimal GPV sequence

From Xenharmonic Wiki
Jump to navigation Jump to search

Is "Val list" the best name for this thing?

I note that this isn't really a list of maps ("vals"), like 12 19 28], but actually a list of ETs given in wart notation. So I could see this being called an "ET list", with the other distinguishing facts left opaque (those being that they are [a] only ETs whose maps are uniform maps ("GPVs") and [b] where each subsequent map improves upon TE error). Unless some people don't consider e.g. 17p to be a different ET from 17c, but only different maps for the same ET, but then that's getting pretty philosophical I think. Or the title could attempt to convey both those facts, such as "Error-decreasing GPV sequence" (though of course I would prefer my own term "uniform map", I understand I should defer to the convention here.) --Cmloegcmluin (talk) 17:47, 18 November 2021 (UTC)

You're right. Val list isn't the best name for this thing. Imo list should be avoided and sequence is a good substitute. ET sequence is a name I reckon very proper. I'm afraid further constraints like error-decreasing or GPV are less essential, but are somewhat heuristic choices that help to shape a neat sequence. The error-decreasing constraint is good at limiting the length of the sequence. It's possible to make another sequence that's quite similar but different – the MOS numbers for the optimal tuning. The GPV constraint is handy in that it makes the sequence terminate. FloraC (talk) 19:14, 18 November 2021 (UTC)
Oh, interesting — I didn't know the GPV constraint made the sequence terminate. Reviewing your code, it looks more like one of a couple arbitrary thresholds/ranges are ending the search; even `find_next_gpv` doesn't seem to have an exit condition related to having found the final GPV. But perhaps I'm misinterpreting one or many things here :) When you have a minute, would you be able to explain how/why this is or what you meant? And also, does the article need a correction with regards to that fact, then? I wrote, "No standard beginning or ending cutoff to the list has been specified", but if the GPV constraint forces termination, then I'd think that'd constitute such a "standard ending" to the list.
After I understand this particular detail, I'll make a brief post on the Facebook Xenwiki Work Group and the Discord wiki channel to see if anyone has any dispute with renaming this "ET sequence", which I agree should suit this feature well (and better than "val list"). --Cmloegcmluin (talk) 19:36, 23 November 2021 (UTC)
The sequence "terminates" as no more GPVs turn up after a sufficiently large index. Any temperament has a fixed error, whereas the sequence of all GPV's errors converges to zero, so all GPVs has less error than the temperament past a certain point. Obviously my code doesn't know it, and you must set the range yourself. FloraC (talk) 21:28, 23 November 2021 (UTC)