Re: Re: Fixed precision numbers

It's not that simple. sprintf rounds mathematically (rounding .5 up or down, depending on... I think whether the integer portion is odd or even).

for (0.35,0.45){print sprintf("%.1f",$_);print "\n"}
# result:
0.3 
0.5
[download]

That won't work for accounting: you always need to round up.

Dave

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Re: Re: Re: Fixed precision numbers by Juerd (Abbot) on Feb 25, 2003 at 22:39 UTC
That won't work for accounting: you always need to round up. No, it won't work for maths, but it will work for accounting. I think it was merlyn who told me sprintf's rounding was called "Banker's rounding" and showed me why it was important. Google has a lot of information about this phenomenon. In short: halves are rounded towards the nearest even integer, and that solves a lot of problems. I don't know about international accounting differences, but I don't think biasing rounding up is a good thing to do. Juerd - http://juerd.nl/ - spamcollector_perlmonks@juerd.nl (do not use).	[reply]
Re: Re: Re: Re: Fixed precision numbers by dash2 (Hermit) on Feb 25, 2003 at 23:15 UTC
Sounds like we need someone with accounting knowledge to deliver wisdom.... Interesting, anyway. dave hj~	[reply]