[x3d-public] Using c# with graphics

[Konstantin Smirnov]

By the way, can we get guaranteed accuracy of math computations, also sums,
division get 16 digit true?

вт, 21 сент. 2021 г., 16:45 Konstantin Smirnov <
konstantin.e.smirnov at gmail.com>:

> Now taking part in a contest, want to understand, is this simple?
> Most examples sum numbers simply
>
> вт, 21 сент. 2021 г., 16:39 Konstantin Smirnov <
> konstantin.e.smirnov at gmail.com>:
>
>> It seems to me that we must not do additional operations on each calc
>> Examples don't have this
>>
>> вт, 21 сент. 2021 г., 13:39 vmarchetti at kshell.com <vmarchetti at kshell.com
>> >:
>>
>>> This reference:
>>> https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/builtin-types/floating-point-numeric-types
>>> details that in the Microsoft .NET C# environment, the numeric double
>>> type is an 8-byte representation, and offers about 16 digits of precision.
>>>
>>> In my experience, in those specific cases where numeric precision needs
>>> to be carefully dealt with, the solution is not to round the results of a
>>> calculation; rather the solution is to look at where two double values are
>>> being compared for equality, and replacing the comparison
>>>
>>> if ( a==b) { .... }
>>>
>>> with
>>> if ( abs(a-b) < tolerance ) { ... }
>>>
>>> and choosing a value of tolerance is can be something like
>>>
>>> double tolerance = 1.0e-15 * Math.Max( abs(a), abs(b))
>>>
>>> Vince Marchetti
>>>
>>>
>>> On Sep 21, 2021, at 1:04 AM, Konstantin Smirnov <
>>> konstantin.e.smirnov at gmail.com> wrote:
>>>
>>> Hi
>>> When adding double numbers in .cs script, must we think about every
>>> digit accuracy, or it's approximate numbers, so we can treat them as
>>> approximate with e-7, or so? 15?
>>>
>>> Can we do calc and round afterwards?
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