Re: Calculation gives wrong result

[Jon Paris <jon.paris@xxxxxxxxxxxxxx>]

Nothing unusual - it is based on trying to maintain maximum accuracy within the bounds of the 63 digit maximum precision. It is all spelled out in the manual https://www.ibm.com/docs/en/i/7.5?topic=expressions-precision-rules-numeric-operations <https://www.ibm.com/docs/en/i/7.5?topic=expressions-precision-rules-numeric-operations>

The only real difference from other languages with decimal precision rules (like COBOL and PL/I for example) is the option to use ResDecPos which ensures that a minimum decimal accuracy is maintained at the potential expense of integer capacity.  ResDecPos in my opinion makes RPG behave more as you would expect - I would love for it to have been the default but lost that battle.  Basically the default is PL/I behaviour and ResDecPos is COBOL.  


Jon P.

> On Aug 29, 2022, at 6:46 PM, Don Brown via RPG400-L <rpg400-l@xxxxxxxxxxxxxxxxxx> wrote:
>
> Hi Jon
>
> Just curious for the intermediate calculation what precision is used ? 
> (Not that it would make much difference unless zero decimal places)
>
> Cheers
>
> Don
>
>
>
>
>
> From:   "Jon Paris" <jon.paris@xxxxxxxxxxxxxx>
> To:     "RPG programming on IBM i" <rpg400-l@xxxxxxxxxxxxxxxxxx>
> Date:   30/08/2022 08:32 AM
> Subject:        Re: Calculation gives wrong result
> Sent by:        "RPG400-L" <rpg400-l-bounces@xxxxxxxxxxxxxxxxxx>
>
>
>
> RPG rules are the same as COBOL.
>
>
> Jon P.
>
> > On Aug 29, 2022, at 5:37 PM, Jack Woehr via RPG400-L 
> <rpg400-l@xxxxxxxxxxxxxxxxxx> wrote:
> > In COBOL, the precedence of math operators is PEDMAS:
> > *() ** / * + -*
> >
> > In RPG, multiplication and division have equal precedence, so the first
> > encountered is the first executed
> >
> >
> > On Mon, Aug 29, 2022 at 2:57 PM Justin Taylor <jtaylor.0ab@xxxxxxxxx> 
> wrote:
> > > Both of these should give 4:
> > > 7 * (4 / 7)
> > > 7 * 4 / 7
> > >
> > > RPG gives 3 and 4 as the result.  I assume it has something to do with
> > > intermediate result variables, but I can't see how.  Can someone 
> explain?
> > >
> >
> > -- 
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