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A comment on Common Lisp: Numbers. Parent comment

Re:Common Lisp: Numbers by rocqua on Friday June 14, 2019 @06:16PM (#20187103)
Interesting caveat to the computable reals. Equality is hard. I need to look into this but I'm pretty sure it's undecidable.

Edit: looking into it was just reading futher on wikipedia. Even ordering is undecidable.

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Re:Common Lisp: Numbers by empath75 on Friday June 14, 2019 @08:32PM (#20187756)
Undecidable in principle but I wonder how much it comes up in practice.
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Re:Common Lisp: Numbers by reikonomusha on Friday June 14, 2019 @10:05PM (#20188026)
In practice, you get guarantees “up to precision”. This is totally reasonable. If you’re doubtful, you can either prove theorems, or bump up the precision.

In general this works well.

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Re:Common Lisp: Numbers by rocqua on Saturday June 15, 2019 @07:11AM (#20189451)
Good point. It's not worse than floating point numbers.
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