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9999999999999999.0 – 9999999999999998.0

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Re: 9999999999999999.0 – 9999999999999998.0

#41

Post by misterdoubt »

seanalltogether wrote: post #13

Are there any mainstream languages that consider a decimal number to be a primitive type? I feel like floating point numbers are far less meaningful in every day programs. Even 2d graphics would be easier with decimal numbers. Unless you're using numbers that scale from very small to very large, like 3d games or scientific calculations, you don't actually want to use floating point.

Depends how you define 'primitive type.' A decimal number is built-in for C# and comes along with the standard libraries of Ruby, Python, Java, at least.

Re: 9999999999999999.0 – 9999999999999998.0

#42

Post by twtw »

mabbo wrote: post #37
alanfranz wrote: post #11

What is the "right answer"? Is the article claiming that such languages don't respect IEEE-754, or that IEEE-754 is shit? If you want arbitrary precision, use an arbitrary precision datatype. If you use fixed precision, you'll need to know how those floats work. Pointless article, imho.

The point is to illustrate a simple fact that most of us know- but maybe some don't. https://m.xkcd.com/1053/

It doesn't even illustrate that particularly well. As is, the page just seems to be pointing at floating point and yelling "wrong", with no information on what's actually happening.

By all means embrace the surprise and educate today's 10,000, by why not actually explain why these are reasonable answers and the mechanics here behind the scenes?

Re: 9999999999999999.0 – 9999999999999998.0

#43

Post by mcguire »

alanfranz wrote: post #11

What is the "right answer"? Is the article claiming that such languages don't respect IEEE-754, or that IEEE-754 is shit? If you want arbitrary precision, use an arbitrary precision datatype. If you use fixed precision, you'll need to know how those floats work. Pointless article, imho.

I think the surprise was that Go uses arbitrary precision for constants.

Re: 9999999999999999.0 – 9999999999999998.0

#44

Post by DougBTX »

svat wrote: post #15

A useful website for these that I ran across recently: https://float.exposed/ For example, entering 9999999999999999.0 into "double" gives https://float.exposed/0x4341c37937e08000 and entering 9999999999999998.0 gives https://float.exposed/0x4341c37937e07fff My wishlist for such a page would contain two additional features: 1. Allow entering expressions like "a OP b == c", so that one can enter "0.1 + 0.2 == 0.3" or…

> 9999999999999999.0 into "double" gives https://float.exposed/0x4341c37937e08000

Nice that it reformats the input to "10000000000000000.0", gets the point across that a 64 bit double float just doesn't have enough bits to exactly represent 9999999999999999.0, but that it does happen to be able to represent 9999999999999998.0.

Re: 9999999999999999.0 – 9999999999999998.0

#45

Post by lozenge »

seanalltogether wrote: post #13

Are there any mainstream languages that consider a decimal number to be a primitive type? I feel like floating point numbers are far less meaningful in every day programs. Even 2d graphics would be easier with decimal numbers. Unless you're using numbers that scale from very small to very large, like 3d games or scientific calculations, you don't actually want to use floating point.

Cobol?

Re: 9999999999999999.0 – 9999999999999998.0

#46

Post by twtw »

seanalltogether wrote: post #13

Are there any mainstream languages that consider a decimal number to be a primitive type? I feel like floating point numbers are far less meaningful in every day programs. Even 2d graphics would be easier with decimal numbers. Unless you're using numbers that scale from very small to very large, like 3d games or scientific calculations, you don't actually want to use floating point.

Julia has built in rationals (as do a few other languages).

I'm not aware of any language (other than Wolfram) that defaults to storing something like 0.1 as 1/10 - i.e. uses the decimal constant notation for rationals, rather than having some secondary syntax or library.

Re: 9999999999999999.0 – 9999999999999998.0

#48

Post by jimhefferon »

seanalltogether wrote: post #13

Are there any mainstream languages that consider a decimal number to be a primitive type? I feel like floating point numbers are far less meaningful in every day programs. Even 2d graphics would be easier with decimal numbers. Unless you're using numbers that scale from very small to very large, like 3d games or scientific calculations, you don't actually want to use floating point.

Racket: https://docs.racket-lang.org/guide/numbers.html

Re: 9999999999999999.0 – 9999999999999998.0

#49

Post by csours »

Retric wrote: post #38
alanfranz wrote: post #11

What is the "right answer"? Is the article claiming that such languages don't respect IEEE-754, or that IEEE-754 is shit? If you want arbitrary precision, use an arbitrary precision datatype. If you use fixed precision, you'll need to know how those floats work. Pointless article, imho.

There are several. If you subtract two numbers close to each other with fixed precision you don’t know what the revealed digits are. (1000 +/- .5) - (999 +/- .5) = 1 +/- 1. Thus 0, 1, and 2 are all within the correct range.

What does revile mean in this context?
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