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A comment on Free42 is a re-implementation of the HP-42S Scientific Programmable Calculator. Parent comment

Re:Free42 is a re-implementation of the HP-42S Scientific Pr... by nvy on Friday May 12, 2023 @01:57AM (#35912469)
The way you're using "decimal floating point" seems to imply there is a "floating point" that is not "decimal".

My understanding is that "decimal", in the context of programming, is a less-precise term to mean floating-point (i.e. encompassing IEEE 754 floats, double- vs single-precision, etc), because they're all binary numbers if you dig deep enough, right?

But apparently I am incorrect/underinformed about this.

What is "decimal", then?

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Re:Free42 is a re-implementation of the HP-42S Scientific Pr... by Thorrez on Friday May 12, 2023 @02:08AM (#35912555)
Decimal means base 10. Decimus is the Latin word for 10, and deci- is the SI prefix for 1/10, e.g. decimeter is 1/10 of a meter. Decimal floating point is x*10^y whereas binary floating point is x*2^y . Compare to hexadecimal which means base 16.
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Re:Free42 is a re-implementation of the HP-42S Scientific Pr... by nvy on Friday May 12, 2023 @02:39AM (#35912768)
Derp. I misunderstood.
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Re:Free42 is a re-implementation of the HP-42S Scientific Pr... by zokier on Friday May 12, 2023 @03:44AM (#35913200)
IEEE-758 floating point standard defines decimal formats, decimal128 is relevant here, I believe that is what free42 uses: https://en.wikipedia.org/wiki/Decimal128_floating-point_form...
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