Implement two-output division

[Chris00]

This implements two-output division as discussed in #87

[unageek]

Hi! Thank you for the PR! Could you generate tests for mul_rev_to_pair following the instructions below?

1. pushd ITF1788
2. git fetch upstream (whatever you named https://github.com/unageek/ITF1788)
3. git checkout inari-pr-89
4. popd
5. ./tools/gen_itf1788_tests.sh
6. cargo fmt
7. Uncomment the next line:
   

   inari/tests/itf1788.rs

   Line 22 in 7b897c4

   //mod libieeep1788_mul_rev;

[Chris00]

I've done so.

[Chris00]

Rebased.

[unageek]

Could you revert the change to .github/workflows/build.yml?

[coveralls]

Pull Request Test Coverage Report for Build 4352295643

• 124 of 124 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.3%) to 85.212%

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Totals
Change from base Build 4331625234:	0.3%
Covered Lines:	2172
Relevant Lines:	2213

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💛 - Coveralls

[Chris00]

Could you revert the change to .github/workflows/build.yml?

I deleted the relevant commit.

[Chris00]

I performed the requested changes. Did not find how to test the KaTeX doc however.

[unageek]

You can build the documentation with:

RUSTDOCFLAGS="--cfg docsrs --html-in-header /path/to/inari/src/_docs/header.html" cargo doc --open

Note that the path to header.html must be absolute.

[unageek]

By the way, do you have any ideas about how the decorated version of mul_rev_to_pair might be used?

[Chris00]

You can build the documentation with:

Thanks — I should have reread the README! (I made a shell script to stop forgetting. 🤞)

do you have any ideas about how the decorated version of mul_rev_to_pair might be used?

No. Actually, books and papers in my field (computer assisted proofs) seldom mention decorated intervals. Maybe in constraint-satisfaction problems but I am less familiar with that.

[unageek]

Could you enhance the documentation in two points?

• Emphasize the difference between division and reverse multiplication.
  • Users may take the word two-output division literally. (It might be better to avoid that expression?)
• Explain how the decorated version of the function is defined.

[Chris00]

I've done so. Let me know what you think.

[unageek]

Thank you so much! Please check some more comments.

[unageek]

GAOL uses the term relational division. I love this one! I'm not going to use it in the crate documentation, though.

[unageek]

LGTM! Thank you!