[ruby-core:74924] [Ruby trunk Feature#12217] Introducing Enumerable#sum for precision compensated summation and revert r54237

Issue #12217 has been updated by Akira Tanaka.


Array#sum is accepted by matz at
https://bugs.ruby-lang.org/issues/12222#note-6

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Feature #12217: Introducing Enumerable#sum for precision compensated summation and revert r54237
https://bugs.ruby-lang.org/issues/12217#change-58054

* Author: Kenta Murata
* Status: Assigned
* Priority: Normal
* Assignee: Yukihiro Matsumoto
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In this issue I propose to introduce Enumerable#sum for precision compensated summation of an array of floating point numbers.

In r54237, I've changed Enumerable#inject to support precision compensated summation for summing up floating point numbers.
But I noticed that this commit broke the equality of `ary.inject(:+) == ary.inject {|a, x| a + x }`.
I think this equality is important property of inject method, so I don't want to break it.

And because precision compensated algorithms are complicated, I think they are provided in the standard library, especially simple summation.


---Files--------------------------------
inject-plus.txt (1.21 MB)


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