Can anyone shed any light on this (I find the documentation for printf and sprintf to be particularly vague...):

for my $num ( 0 .. 101 ) {
   $num += 0.005;
   printf "%.2f\n", $num;
}

[download]

Output: I get (using ASP 5.61, WinXP):

0.01
1.00
2.00
3.00
..
8.01
..

[download]

followed by seemingly random series of x.00 or x.01. Interestingly(?), if I change the number of decimals that I want to round to:

for my $num ( 0 .. 101 ) {
   $num += 0.0005;
   my $result = sprintf "%.3f", $num;
   print "$result\n";
}

[download]

I get similarly strange results, but not for the same 'numbers' (eg I get 2.001 and 3.001, as compared with 2.00 and 3.00 in the first case

Am I missing something (as usual)?

tia, dave

In reply to (s)printf and rounding woes by Not_a_Number

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