A word for a value between 0 and 1 (inclusive)

“mantissa” (https://en.wikipedia.org/wiki/Common_logarithm#Mantissa_and_...) comes close, but excludes 1.

IEEE 754 sort-of has that as a part of a float, too (https://en.wikipedia.org/wiki/Significand), and people use the term “mantissa” for it, but it has to special-case 0.

⇒ barring better suggestions, I think I would stretch the definition of mantissa a bit further.

Off-topic, but the wonderfully specific word "mantissa" comes up so infrequently that I just have to share this painting [0] of mine that features it.

[0] https://www.curtiswmoore.com/image_detail.php?title=manta.jp...

How about just oTo1InclusiveVal ? I know very simple, but would get the job done ?

I would actually call this a bit of an antipattern.

`accuracy` seems fine to me -- although a more descriptive function name than `FuncName` might suggest a better parameter name as well.

Digging through the dictionary to find the perfect word means that whoever reads this code is likely going to have to do the same -- why would you ask them to do that?

If you aren't referring to a common mathematical or physical concept, and the word you need it isn't a part of your domain language, you're better off with "accurate but slightly vague" over "almost precise" or "precise but obscure".

It seems like the author's need would be better met by readable tests, guard conditions, and -- if this is part of an API -- documentation that describes how `accuracy` is used.

What about "fraction"? That's what I tend to use in my own code, although it could be greater than 1 potentially.