why 1-0.4 = 0.6 vs 1 - 1.4 = -0.399999999999 and 0.1 - 0.5 = -0.4 vs 0.2 - 0.6 = -0.3999999 How to make the calculation consistent? What the best way to deal with that to be able to compare (0.2 - 0.6) == (0.1 - 0.5) to get true, not false as it is right now Julia ver 1.11.5

Floating Point Math Also PSA: floating-point arithmetic

Mose’s answer is what you need to read, but also just to directly answer your question [image] BMval: What the best way to deal with that to be able to compare (0.2 - 0.6) == (0.1 - 0.5) to get true, not false as it is right now julia> (0.2 - 0.6) ≈ (0.1 - 0.5) true (that’s \approx<TAB>)

Oh, that question wasn’t there when I replied :sweat_smile:

To build on previous answers: checking for precise equality in floating point math should be used in only specific situations and with an understanding of roundoff as you see it here. The issue is that the decimal system used by humans is not perfectly matchable by the base-2 floating point system m…

Why 1-0.4 = 0.6 vs 1 - 1.4 = -0.399999999999

General Usage

giordano May 19, 2025, 2:37pm 2

Also PSA: floating-point arithmetic

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Why 1-0.4 = 0.6 vs 1 - 1.4 = -0.399999999999

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