Hi,

I'm pretty sure that your expectation of the result of

print sprintf("%0.02f",0.345);

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is a little bit wrong. 0.345 rounded to two digits after the comma is 0.35 and not 0.34. You hit a classical floating point rounding error, Have a look at:

perl -E 'print sprintf("%0.18f",0.346);'

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If you do mathematics with this kind of rounding error you can be hit by such a phaenomena.

UPDATE: Look at this:

#!/usr/bin/env perl
use strict;
use warnings;
use 5.010;
use Data::Dumper;

my $l8 = 3.49;
my $l7 = 2;

my $subprice = 1.4;
my $tprice;

$tprice = ($l8/$l7)-$subprice;
if ($tprice < 1  && length($tprice) > 4) {
    print "SPRINTF - $tprice -  " . sprintf("%0.18f",$tprice) . "\n";
}

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McA

In reply to Re: Printf/Sprintf Behavior Change by McA
in thread Printf/Sprintf Behavior Change by stingles

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