Why does 0.1 and 0.2 = 0.30000000000000004?

Re:Why does 0.1 and 0.2 = 0.30000000000000004? by ezfe on Wednesday February 08, 2023 @01:54PM (#34712883)

Numbers (from Apple) returns TRUE for both expressions you list

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Re:Why does 0.1 and 0.2 = 0.30000000000000004? by Kon-Peki on Wednesday February 08, 2023 @02:27PM (#34713462)

Objective-C has a really nice decimal math library. Last I looked (it’s been a while), Swift didn’t. It might have one by now.

Years ago, I had a few apps in the App Store that made extensive use of it. It really was very nice to work with.

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Re:Why does 0.1 and 0.2 = 0.30000000000000004? by arcticbull on Wednesday February 08, 2023 @02:51PM (#34713870)

Swift has the same functionality in the Decimal type.

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Re:Why does 0.1 and 0.2 = 0.30000000000000004? by Kon-Peki on Wednesday February 08, 2023 @03:15PM (#34714273)

Thanks! It looks like that was added in Swift 3. That was a long time ago. I guess I’m just really old ;)

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Re:Why does 0.1 and 0.2 = 0.30000000000000004? by sheetjs on Wednesday February 08, 2023 @02:17PM (#34713287)

Under the hood, modern Numbers stores values in Decimal128 (16 bytes)

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Re:Why does 0.1 and 0.2 = 0.30000000000000004? by Salgat on Wednesday February 08, 2023 @04:35PM (#34715576)

So people understand, Decimal type is not fixed point, but rather is a floating-point type that uses base 10 instead base 2. This means that if you do 1.0/3.0*3.0, you still get 0.999999~.

Example: http://tpcg.io/_A0IXQJ

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