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On Sat, Aug 22, 2015 at 1:32 PM, Alan McKinnon <alan.mckinnon@×××××.com> wrote: |
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> I can tell you that equality comparisons on floats are problematic, and |
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> always will be due to how they are stored (double-precision floats, |
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> inhernetly inexact). This is not a "problem" per se, it's a systemic |
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> side effect of how our computers represent floats i.e. you can't "fix" |
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> it as there is nothing to fix |
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It's not that floats are inherently "inexact"; it really has to do |
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with trying to represent a base-10 number in a data structure designed |
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to hold a base-2 number. |
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If your number can be represented by some multiple of a power of 2, |
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equality comparisons will work. If it cannot be, it has to be stored |
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as an approximation. |
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Someone else mentioned a "decimal" data type, which works much like a |
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float but is designed for storing base-10 numbers. |
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