That's strange. Here's the version of perl I ran it on originally

C:\>perl -v

This is perl, v5.8.4 built for MSWin32-x86-multi-thread
(with 3 registered patches, see perl -V for more detail)
Copyright 1987-2004, Larry Wall

Binary build 810 provided by ActiveState Corp.

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I just ran it on 5.8.4 on debian - then 5.00503, 5.8.2 and 5.8.5 on FreeBSD. All versions round both 1.5 and 2.5 to 2

Does anyone else get something different? 

for ($i=0;$i<10;$i+=.5){
    printf "%.1f: %.0f\n", $i, $i;
}
__END__
Output:
0.0: 0
0.5: 0
1.0: 1
1.5: 2
2.0: 2
2.5: 2
3.0: 3
3.5: 4
4.0: 4
4.5: 4
5.0: 5
5.5: 6
6.0: 6
6.5: 6
7.0: 7
7.5: 8
8.0: 8
8.5: 8
9.0: 9
9.5: 10

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In reply to Re^3: Rounding error? by bmann
in thread Rounding error? by dracos

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