[SystemSafety] Accuracy of COVID modeling code

[Peter Bishop]

Exact results are pretty unlikely for FP.
But on the other hand, I think the *numerical algorithm* is probably
more important than any local HLL optimisations in reducing rounding
errors,
e.g. when adding an array of FP numbers, the best option is to sort them
an ascending order before sequentially adding them.

Peter Bishop

On 09/05/2020 18:21, Peter Bernard Ladkin wrote:
>
> On 2020-05-09 18:41 , Derek M Jones wrote:
>> Section 5.1.2.3 of the C Standard,
>>
>> or sentence 189: https://c0x.coding-guidelines.com/5.1.2.3.html
>> "In the abstract machine, all expressions are evaluated as specified by the semantics."
> Which should mean that the expression "x^2 - y^2" returns the square of the value of x minus the
> square of the value of y. What is called the exact value.
>
> What a poor piece of writing.
>
> PBL
>
> Prof. Peter Bernard Ladkin, Bielefeld, Germany
> Styelfy Bleibgsnd
> Tel+msg +49 (0)521 880 7319  www.rvs-bi.de
>
>
>
>
>
>
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Peter Bishop
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