0.1 + 0.2 = 0.30000000000000004

[realeatham]

Describe the bug
See title

To Reproduce
See title

Expected behavior
The sum to equal 0.3

Screenshots
If applicable, add screenshots to help explain your problem.

Smartphone (please complete the following information):

• Device: s21
• OS: android 14 I think
  -app Version: 2.7.1

Additional context
Could also be a problem with keval @notKamui

[sosauce]

https://discuss.kotlinlang.org/t/kotlin-compiler-apparently-losing-double-value-precision/14076

See this, I think it's "normal" and nothing we can do about it

[sosauce]

https://floating-point-gui.de/

[sosauce]

Oh wait, I could make it refactor or sum but do I really want to?

[notKamui]

@realeatham this is completely normal behavior for floating point arithmetic in binary representation. Please try that in many other languages and you'll see the same result.

@sosauce you should close this issue.

[SlamaFR]

@realeatham So this is basically a well known issue of floating point numbers in computer science.

See https://en.wikipedia.org/wiki/IEEE_754#Rounding_rules

[Oliveoilfly]

Hello!

I disagree with @notKamui: yes, indeed, this is true in regular float arithmetic, but there is also fixed-point math.

@sosauce, therefore, I suggest reopening this issue and rewriting the math in BigDecimal. Since these aren't high-load calculations, there won't be a noticeable performance difference.

[notKamui]

Hi @Oliveoilfly if I find the time and motivation to work on the Keval project again, and finally fix the publication to maven central, I will probably also make a way for BigDecimal to be used instead of Double, or any number-like type really.

@sosauce you may re-open the issue and file an issue on Keval about this, linking to this comment

[hewantstocomment]

I guess it's the same problem...
Expexcted result of 8+12+8+22.12 is 50.12 ...
Device: Pixel 8a on GrapheneOS. Everything up-to-date.
Maybe add a warning to the app?
e.g. in the description of the app-stores and here write that: there is some limitation when it comes to decimal numbers usw.

Anyway, thanks for the app and your work!