Re: Fixed vs float and precision and conversions

["Björn Lundin" <b.f.lundin@gmail.com>]

Den 2020-07-08 kl. 22:34, skrev Niklas Holsti:

> 
> No, see below. You are confusing decimal (base-10) reals with binary 
> (base-2) floats.

Yes.

>> It is at least not certain that the number expressed in fixed_type is 
>> one of them in the array below.
>> And that is my real problem - I think.
> 
> 
> That is certainly true -- if you don't know anything about the Float 
> number, then you won't know much about the result of Fixed_Type'Round on 
> that Float number. If you want to be sure that the result is one of the 
> numbers in your table, you have to check.
> 

yes - I realize that


> 
> But the values in the Global_Odds table are all given with two decimals, 
> not three, so why not define Fixed_Type with delta 0.01, which avoids 
> this possible Float precision problem, as well as being more apt?

Because I wanted to express 6.5% -> 0.065 in fixed_type as well.
I think I mentioned that in a post.

Fixed_type is used generally here (in this system) instead of float, not 
only for that array.

This may have been a bad design choise though.

-- 
Björn