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From: =?UTF-8?Q?Bj=c3=b6rn_Lundin?= <b.f.lundin@gmail.com>
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Subject: Re: Fixed vs float and precision and conversions
Date: Thu, 9 Jul 2020 09:23:30 +0200
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Den 2020-07-09 kl. 08:20, skrev Dmitry A. Kazakov:
> On 08/07/2020 21:41, Björn Lundin wrote:
> 
>> As I replied to Niklas:
>> It is at least not certain that the number expressed in fixed_type is 
>> one of them in the array below.
> 
> The array has varying step 0.01 to 10.0, your test has step 0.001. What 
> do you expect? Of course it must fail at a very high rate from 9/1 to 
> 999/1, practically always.
> 

welll, in practice not always.
It only fails when - like my example -

Fixed_Type(float(5.10)) becomes 5.099

and its been running with that construct since 2014,
and I only noticed now. So - not always, actually very seldom.

I did expect floating comparison error to go away using fixed type,
but I forgot about 'garbage in -> garbage out'

I don't have that kind of rounding errors once the values are converted 
to fixed_type but I did not realize that I had them in the conversion.

-- 
Björn