Trivial divide calculations generate results with rounding errors

[garycmartin]

Trivial divide calculations are showing rounding errors (tested in Calculate-33).

89 / 100 = 0.890000000
496 / 100 = 4.95999999

Trying the same calculations in a terminal with python is fine 89 / 100 = 0.89, and 496 / 100 = 4.96.

If I try using multiply instead, the answers are accurate.

89 * 0.01 = 0.89
496 * 0.01 = 4.96

[greenfeld]

Is Calculate using an arbitrary precision numeric engine {python's Decimal type}, or just doing floating point math via eval() or similar?

If it is not doing the former, Calculate probably should do this, as at least a one other software calculator tool I know moved to an arbitrary precision approach to avoid these sorts of quirks.

[godiard]

This ticket can be related to #2697

[miguelgarcia]

patch for this issue

[garycmartin]

Thanks again Miguel, this patch is now also in mainline.

 http://git.sugarlabs.org/calculate/mainline/commit/a2cbde202c7450b12b118b688d8399a6c836ca10