• cynar@lemmy.world
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    11 months ago

    For those confused

    2.25+2.25=4.5 rounds to 2+2=5

    2.5+2.5=5 truncates to 2+2=5

    Both can crop up in programming, depending on the situation.

    • Echo Dot@feddit.uk
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      11 months ago

      2.25 + 2.25 = 4.5

      If you add two floats together then the output is a float, if you add an int and a float together the output is a float. Computers will always perform the calculation as is, unless you explicitly tell them to perform a rounding operation.

      • cynar@lemmy.world
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        11 months ago

        However, if you stuff them into an int at the last minute, you can get that effect.

        Under the hood, it’s floats. On the output, it’s ints.

        It’s obvious and silly with small examples. The problem can creep in when you are using larger libraries or frameworks.

    • afraid_of_zombies@lemmy.world
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      11 months ago

      A few months back I had a floating point that had a single 1 like 16 digits past the decimal place and I couldn’t get rid of it.