If 5.24/1 is 5.24 then 1*5.24 = 5.24, so why is 5.24%1 = 0.24? It should be 0, right? Because 1*5.24=5.24? which leads to a zero in remainder?
Does mod only take the int part of a decimal to divide and produce a remainder?
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4Nice numbers in decimal are rarely nice numbers in binary and you see a rounding error. – Thorbjørn Ravn Andersen Jun 29 '20 at 12:03
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But we still love them, most of the time. – Maroun Jun 29 '20 at 12:04
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2I don't get your logic here. `/` is not `%` - those are two totally different operations. – Amongalen Jun 29 '20 at 12:05
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If I understand your reasoning correctly, would you also say that `3 % 2 == 0` since `3 / 2` is `1.5`, which leaves no remainder? – Brian61354270 Jun 29 '20 at 12:06
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@Brian `3/2 == 1` in Java, just saying :) – Amongalen Jun 29 '20 at 12:08
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@Amongalen I'm aware. My comment is intended to highlight the error in the OP's reasoning. – Brian61354270 Jun 29 '20 at 12:08
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the modulo operator (%) should only be applied to integers, so round before. – Donatic Jun 29 '20 at 12:09
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Here is a discussion about that topic. https://stackoverflow.com/questions/46221470/is-it-possible-to-get-the-modulo-with-decimals – Donatic Jun 29 '20 at 12:12
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3Here is a description of how module works on floating points in java. It is not the same as on integers. https://stackoverflow.com/questions/2947044/how-do-i-use-modulus-for-float-double – MTilsted Jun 29 '20 at 12:12
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Yes, the % operator for floating point numbers is so that the modulus is multiplied by an integer.
5.24 % 1 = 0.24 because
5.24 = 5*1 + 0.24
There is a separate issue with rounding error and what numbers can be represented exactly in binary floating point, which makes the result slightly different from 0.24.
Joni
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Thank you for your kind comment. So in short the mod operator in programming doesn't work with the fractional part of a decimal number, correct ? – BatKnight Jun 29 '20 at 12:19
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It does if you use a modulus with a fractional part. `3.625 % 1.25` gives `1.125` because `3.625 = 2*1.25 + 1.125` – Joni Jun 29 '20 at 12:23
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