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Real life example for floating point error

Are there any examples of a company that was burnt with floating point data that caused a rounding issue? We are introducing a new system, and all monetary values ​​are stored in floats. I think that if I can show actual examples of why this failed, it will have more weight than the theory of why values ​​cannot be stored properly.

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These examples are taken from the embedded world (Ariane 5, Patriot), but are not stricto sensu floating point rounding errors. Ariane 5 Error - Error in conversion. Patriot bug was introduced during software adaptation. It includes calculations at different points with an inherent non-representable constant (which turns out to be harmless - 0.10).

There are two problems that I foresee with binary floats for monetary values:

  • decimal values ​​as common as 0.10 cannot be represented exactly.

  • If the accuracy is too low, then what could have been a pure overflow creating an exception becomes an inaccessible loss of accuracy.

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