Re^2: Rounding error?

I'm surprised by your comment, not by the output, seeing as that prints 2 and 3 for me.

ActivePerl 5.6.1
ActivePerl 5.8.0

If it did give 2 for both, I'd be asking: "Can someone explain the sense of a rounding where the following prints 19, not 20:"

$sum += sprintf("%.0f", $_/10) foreach (0..19);
print($sum, $/);
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Re^3: Rounding error? by bmann (Priest) on Oct 19, 2004 at 03:08 UTC
That's strange. Here's the version of perl I ran it on originally `C:\>perl -v This is perl, v5.8.4 built for MSWin32-x86-multi-thread (with 3 registered patches, see perl -V for more detail) Copyright 1987-2004, Larry Wall Binary build 810 provided by ActiveState Corp.` [download] I just ran it on 5.8.4 on debian - then 5.00503, 5.8.2 and 5.8.5 on FreeBSD. All versions round both 1.5 and 2.5 to 2 Does anyone else get something different? `for ($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` [download]	[reply] [d/l] [select]

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Re^3: Rounding error?
by bmann (Priest) on Oct 19, 2004 at 03:08 UTC

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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