Can others reproduce this? I’m getting a strange result when adding 0.1 +0.2 _ _ _ _(_)_ | Documentation: https://docs.julialang.org (_) | (_) (_) | _ _ _| |_ __ _ | Type "?" for help, "]?" for Pkg help. | | | | | | |/ _` | | | | |_| | | | (_| | …

This is the expected behavior for floating-point arithmetic: https://0.30000000000000004.com/

[image] PSA: floating-point arithmetic Offtopic Sometimes people are surprised by the results of floating-point calculations such as julia> 5/6 0.8333333333333334 # shouldn't the last digit be 3? julia> 2.6 - 0.7 - 1.9 2.2204460492503…

I suspect that almost everyone who does computer programming has asked this question once in some forum😁 It comes up again and again. Here’s one write up: [image] PSA: floating-point arithmetic Offtopic Sometimes people are surprised by the results of floating…

Thank you … I had no idea… rather fascinating

For even more fun, check out how tricky rounding is: julia> (round(-0.5), round(0.5)) (-0.0, 0.0) Python 3.10: >>> (round(-0.5), round(0.5)) (0, 0) Python 2.7: >>> (round(-0.5), round(0.5)) (-1.0, 1.0) Javascript (in Edge): > with(Math){ [round(-0.5), round(0.5)] } < [-0, 1]

In Julia, we can access the distinct rounding modes. julia> (round(Int, -0.5), round(Int, 0.5)) (0, 0) julia> M = RoundToZero RoundingMode{:ToZero}() julia> (round(-0.5, M), round(0.5, M)) (-0.0, 0.0) julia> M = RoundFromZero RoundingMode{:FromZero}() julia> (round(-0.5, M), round(0.5, M)) (-1.…

It’s completely correct (given it’s assumptions) for Float64/IEEE. You can do accurately with rationals (in Julia, and in Raku, formerly Perl 6, rationals are the default number type), with: julia> 1//10 + 2//10 # Rational math is slower 3//10 julia> Float64(1//10 + 2//10) # You can print out i…

[image] uniment: For even more fun, check out how tricky rounding is: That’s not tricky because of floating point numbers, there are simply different decisions taken because rounding isn’t unequivocally defined. That has nothing to do with floating point arithmetic, half integers are exactly …

Incorrect summation of Float64

General Usage

John_Gibson January 22, 2023, 11:02pm 4

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Incorrect summation of Float64

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