Hi
I know lots of floats are impossible to represent in 32bit IEEE754, but why is this rounding not preserved through simple arithmetic?
aka print $num is correct
but not print $num-int($num);

What is the easiest way to get rid of those?

$fracstr = sprintf("%.3f",$frac) ? 

$ ./nice_num.pl
1234.123 = 1234 0.123000000000047
1000 = 1000 0
0.234 = 0 0.234
4.222 = 4 0.222
130.000 = 130 0
500 = 500 0
345678.345 = 345678 0.34499999997206

[download]

----------------------------------------------------

#!/usr/bin/perl -w

##################################
# split number in int and fraction
my $split_number = sub {
    my $num = shift;
    my $int = int($num);
    my $frac = $num - $int;
    return [$int,$frac];    
};

# main
my @testnums = qw(1234.123 1000 0.234 4.222 130.000 500 345678.345);
for $n (@testnums) {
    print "$n = ";
    for $z (@{&$split_number($n)}) {
        print "$z ";
    }
    print "\n";
}

[download]

Thanks

20060113 Janitored by Corion: Added formatting, removed PRE tags

In reply to simple arithmetic creates rounding errors by lreplrep

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