Re: DecimalField model validation

2011-10-06 Thread Christophe Pettus
On Oct 6, 2011, at 9:29 PM, Tai Lee wrote: > Why is ROUND_HALF_EVEN superior? ROUND_HALF_EVEN is the standard when doing financial calculations, an extremely common use of DecimalField. -- -- Christophe Pettus x...@thebuild.com -- You received this message because you are subscribed to th

Re: DecimalField model validation

2011-10-06 Thread Tai Lee
Why is ROUND_HALF_EVEN superior? Perhaps for statistics, where rounding all halves up would skew results, but I guess not for most other cases. If the default rounding behaviour produces different results than a regular calculator, common spreadsheet and accounting software or even human (mentally

Re: DecimalField model validation

2011-10-06 Thread Marco Paolini
On 06/10/2011 02:45, Paul McMillan wrote: .. (A) silent rounding issue: when a decimal value is saved in db its decimal digits exceeding decimal_places are rounded off using .quantize(). Rounding defaults to ROUND_HALF_EVEN (python default). There is no mention of this behavior in