[SystemSafety] Accuracy of COVID modeling code

Peter Bishop pgb at adelard.com
Sun May 10 16:54:27 CEST 2020

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
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 of the C Standard,
>> or sentence 189: https://c0x.coding-guidelines.com/
>> "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.
> 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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