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A comment on Computing the number of digits of an integer even faster. Parent comment

Re:Computing the number of digits of an integer even faster by klodolph on Friday June 04, 2021 @12:29PM (#27395332)
I don't have any tips. Micro-optimization at this level often requires creative leaps, and proving that they work can be tricky (although for 32-bit integers, you can just iterate over all of them to validate). There are web pages with "bit-twiddling hacks" (https://graphics.stanford.edu/~seander/bithacks.html), and sometimes you can find a solution for your problem with a superoptimizer (if you care enough).
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Re:Computing the number of digits of an integer even faster by knuthsat on Friday June 04, 2021 @12:47PM (#27395572)
One other way to prove these algorithms is by writing them in z3 prover. You write a simple one that is 100% correct and then you prove equality for your optimized one or find an example that will show inequality.
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Re:Computing the number of digits of an integer even faster by chrisseaton on Friday June 04, 2021 @12:59PM (#27395747)
A great thing about a monadic operation that takes a 32-bit integer, like this one, is that you can also just exhaustively test it in reasonable time!
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Re:Computing the number of digits of an integer even faster by Dylan16807 on Friday June 04, 2021 @03:37PM (#27398129)
Today I learned "monadic" has two significantly different meanings in the realm of programming.

I'm only familiar with using "unary" to mean single-parameter.

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Re:Computing the number of digits of an integer even faster by Filligree on Friday June 04, 2021 @05:13PM (#27399140)
Nah, they’re pretty much the same meaning.
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Re:Computing the number of digits of an integer even faster by Dylan16807 on Friday June 04, 2021 @05:33PM (#27399309)
A monad, derived from monoid, means multiple very specific things completely unrelated to the other definition of "single parameter".

And the etymology is basically a coincidence because "mono" got used in different places, isn't it?

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Re:Computing the number of digits of an integer even faster by a1369209993 on Friday June 04, 2021 @07:14PM (#27400178)
> []completely unrelated[] to the other definition of "single parameter".

Actually, all monads are monadic functions/operators on their (usually type) parameter. Eg, 'list' is a monadic operator from element types to types of lists of those elements.

It's completely different (AFAICT), and mostly unrelated, but it's not completely unrelated.

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