Re: Weird math...

[Bill Stephenson]

on 10/13/03 3:07 PM, John Delacour at [EMAIL PROTECTED] wrote:

> Don't ask me why but this does solve your problem (which happens also
> in 5.8.0):
> 
> @ls = qw(1.655 1.755) ;
> for (@ls) {
> $_ += 0.00000000000001;
> printf "%.2f$/" , $_;
> }
> 
> 
> JD

Thanks JD! That seems to work pretty good. I still don't quite get what's
going on here so I'll do some further testing to see If I can catch any more
odd (imho) behavior. For grins, run the included code and check the
different results for each sub routine.

-- 

Bill Stephenson
www.PerlHelp.com
1-417-546-5593



#################### start code ####################
#!/usr/bin/perl -w

use strict;

my @stuff = qw "1.055
                1.155
                1.255
                1.355
                1.455
                1.555
                1.655
                1.755
                1.855
                1.955
                1.1055";

&round1;

&round2;

&round3;

sub round1 {

print "=============== round1 ================\n";

foreach my $num1 (@stuff) {

     print "$num1 rounded to -> ";

     my $result1 = $num1;

     $result1 = ($result1*100);

     $result1=(int $result1 + ( $result1 > 0 ? 0.5 : -0.5 ))/100;

     $result1 = (sprintf qq~%.2f~, $result1);
     
     print "$result1\n";

     }
}

sub round2 {

print "=============== round2 ================\n";

foreach my $num2 (@stuff) {
    
     print "$num2 rounded to -> ";

     my $result2 = $num2;

     $result2 = ($result2 + .00001);

     $result2 = (sprintf qq~%.2f~, $result2);
     
     print "$result2\n";

     }
}

sub round3 {

print "=============== round3 ================\n";

foreach my $num3 (@stuff) {

     print "$num3 rounded to -> ";

     my $result3 = $num3;

     $result3 = ($result3 + 0.0000000000000001);

     $result3 = (sprintf qq~%.2f~, $result3);
     
     print "$result3\n";

     }
}
##################### end code #####################