Add Array.asformat method and add back reshape function.

[hameerabbasi]

• Fix signed/unsigned integer naming mix-up.
• Add mechanism for detecting output format.

[codspeed-hq]

CodSpeed Performance Report

Merging #800 will not alter performance

_{Comparing hameerabbasi:add-ops (e561587) with main (e111324)}

Summary

✅ 340 untouched benchmarks

[mtsokol]

As #799 is now merged let's rebase it and also include COO in the determine_format function. I think that it could be COO+COO=COO and CSR+CSR=CSR etc.

[hameerabbasi]

As #799 is now merged let's rebase it and also include COO in the determine_format function. I think that it could be COO+COO=COO and CSR+CSR=CSR etc.

Right now COO+COO=DCSR (as both levels are sparse for COO, and I'd like to avoid special cases as much as possible). However; I added an asformat method to convert between formats if we need to.

[mtsokol]

The progress looks good! One more round of comments.

[mtsokol]

I think it's the last round of review - I think test_reshape should be refined to cover most of reasonable scenarios.

And let's push another commit instead of force push.

[mtsokol]

LGTM!

[hameerabbasi]

Thanks for the thorough review, @mtsokol!