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  1. Drools
  2. DROOLS-314

Build in accumulate functions are highly unreliable for long's and BigDecimals

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      When dealing with financial data, one should never ever use double's. Instead BigDecimal should be used.
      Not because BigDecimal is bigger (that's rarely a problem) but because it doesn't do any decimal to binary transformation.
      For example, it's impossible for a double to correctly represent "0.2", aka 1/5.
      Summing many doubles (or even a few differing in scale), can easily give wrong results (and for financial data this tends to be important).

      Using doubles to sum longs have the exact same problem.
      Attached is a testcase patch which proves this by checking if (MAX_LONG - 4L) and 3L sum up to be (MAX_LONG - 1L).
      Currently they don't.

      One possible way to solve this is to fix JBRULES-1075,
      which just happens to give drools-solver 3% more performance what a coincidence ^^

        1. JBRULES-1322-testcase.patch
          7 kB

            Unassigned Unassigned
            gdesmet@redhat.com Geoffrey De Smet (Inactive)
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