• 257m@sh.itjust.works
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    8 months ago
    number % 2 == 0
    and
    (number & 0b1) == 0
    

    Are the only sane ways to do this. No need to floor. Although If its C and you can’t modulo floats then (number/2 == floor(number/2))

      • 257m@sh.itjust.works
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        8 months ago

        Whats the alternative a macro? An inline function is perfectly fine for checking if a nunber is even. Compiler will probably optimize it to a single and instruction.

        • homura1650@lemmy.world
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          8 months ago

          No. The alternative is to not use a float. Testing if a float is even simply does not make sense.

          Even testing two floats for equality rarely makes sense.

          What is the correct output of isEven((.2 + .4) ×10)

          Hint: (.2 + .4) x 10 != 6

          • 257m@sh.itjust.works
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            8 months ago

            It does if it dosen’t have a decimal. If it has decimal then it automatically isn’t and the function will return false. Are you talking about cases like 0.1 + 0.2 equaling 0.3000000004 because that is just due to the nature of floats and there is nothing a function can do other than use larger floats for more accuracy.