Rename chunk_width to samples_chunk_size and chunk_length to variants_chunk_size (or similar)

[jeromekelleher]

I find it unhelpful adding different dimensions here which don't actually line up with the named xarray dimensions. I think we should use the named dimensions here in some way, rather than "length" and "width".

Options:

• chunk_variants, chunk_samples
• variants_chunk_size, samples_chunk_size
• ...

I don't really know what's the best choice here.

Any thoughts @tomwhite @benjeffery?

[tomwhite]

+1 to changing the names. I vote for variants_chunk_size and samples_chunk_size.

[benjeffery]

Yep, agreed that the dimensions should be named

[jeromekelleher]

OK, variants_chunk_size and samples_chunk_size it is. Should be simple search and replace