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by lokedhs 1801 days ago
I personally don't find it important. And I have seen that the demand of having numbers match exactly comes from a misunderstanding of how floating point calculations work.

Sometimes this is understood by the banks and the solution is to implement a tolerance in the comparisons. In other cases other solutions may have to be used, such as forcing certain reports to be computed on certain software/hardware.

1 comments

>I personally don't find it important

You remind me of the alleged UK Post Office scandal:

https://www.bbc.com/news/business-56718036

That's not what I'm talking about. Floating point computations happen when doing risk calculations, for example computing risk numbers in a Black-Sholes calculation.

A difference in the 15'th decimal has no impact on the risk number.

I don't have a good counterexample off hand, but I've seen a web page literally display "NaN" where a number should be.

The truth is, I have faith in Murphy's law.