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A comment on Fast Inverse Square Root. Parent comment

Re:Fast Inverse Square Root by x3n0ph3n3 on Monday November 02, 2020 @07:12PM (#24974950)
Computers do not have _real_ number systems, only _rational_ number systems and rational approximations of real numbers.
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Re:Fast Inverse Square Root by jackpirate on Tuesday November 03, 2020 @01:47AM (#24977066)
There are plenty of libraries for computable numbers [1], which sit between the rationals and reals

[1] https://en.wikipedia.org/wiki/Computable_number

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Re:Fast Inverse Square Root by lifthrasiir on Tuesday November 03, 2020 @02:06AM (#24977170)
...which (naturally) can't determine if some number x is equal to y or not; that alone makes using constructive real numbers challenging and the usage is virtually non-existent. I believe the most-known software using them is the Android calculator since 6.0 and Hans Boehm (of the gc fame) documented various issues encountered [1].

[1] https://dl.acm.org/doi/fullHtml/10.1145/2911981

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