[r-t] Complexity of extents

[Matthew Frye]

On 13 Jun 2013, at 21:46, Mark Davies <mark at snowtiger.net> wrote:
> Philip Earis asks,
> 
>> Are there appropriate standard tests / algorithms
> > that can be used in such a scenario, ie here to
> > rank extents in terms of their intrinsic complexity?
> 
> Find a way of writing out the extents in a standard way (perhaps the expanded place notation), and compress them using a tool like gzip.
> 
> The size of the compressed extent is a metric of its complexity: simpler, more repetitive extents will be smaller.

Yes. Clever. The choice of how to "write out" the extent clearly becomes key, perhaps even moreso than the choice of compression.

I think it's important to keep the relationships you might notice while ringing in this description. e.g. for spliced St Simon's and St Martin's doubles, around the half-lead the back work is the same despite the difference in frontwork, but place notation mangles recognition of that. With any simple, linear description you can get issues like this but if you were to "write out" the method in some 2-D format (e.g. a grid) and then directly compress that by some means it may be more satisfactory.

I doubt simply trying to apply a traditional image compression algorithm to a picture of a grid will get you very far though!

Final thought: it might be interesting to compare scores between different descriptions, might shed light on the most efficient way of learning the particular method.

MF


On 13 Jun 2013, at 17:05, Philip Earis <Earisp at rsc.org> wrote:
> *         What is best to measure for this? Minimal repetition of blocks of notation?  Or can this fall down somehow (eg with the spliced doubles examples, which has a lack of identical patterns but still much structure)?