Rounding Variables

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: Rounding Variables by $code or die (Deacon) on Oct 09, 2000 at 20:36 UTC
Actually if you do that, then you it will not round properly. e.g. it fails in the following examples: $distance=1.0050000 returns $roundeddistance = 1 (should be 1.01) $distance=1.9000000 returns $roundeddistance = 1.9 (should be 1.90) You should use sprintf function to round decimals: `$roundeddistance = sprintf "%0.2f", $distance;` [download] Or, if you want it to to look a bit cleaner (i.e. have a leading '0' - 0.21 instead of .21) then you can use the following: `$roundeddistance = sprintf "%1.2f", $distance;` [download] Hope this helps.	[reply] [d/l] [select]
RE: Re: Rounding Variables by Albannach (Monsignor) on Oct 10, 2000 at 07:49 UTC
Just to keep things straight, to get "0.21" you'd need to use `$roundeddistance = sprintf "%4.2f", $distance;` [download] as the number to the left of the decimal in the format must be the minimum number of characters in the output including the leading zero (if indeed it's a zero) and the decimal. I should also add that rounding is not quite as simple as it first appears, depending on your field of work. For example, some need to always round 0.5 up, but others alternately round up and down in order to reduce the accumulated overestimate error in a sum of such rounded numbers. I've been tripped up by this a number of times...	[reply] [d/l]
Re: Rounding Variables by kilinrax (Deacon) on Oct 09, 2000 at 20:09 UTC
Try this: `$roundeddistance = int($distance*100)/100;` [download] (assuming you want it rounded down, and not padded with zeroes. If not, see $code or die's suggestion below)	[reply] [d/l]
RE: Re: Rounding Variables by Anonymous Monk on Oct 09, 2000 at 20:10 UTC
Perfect.. thanks for the lightning fast help -Dipul	[reply]