sub round($$)
{
sprintf "%.$_[1]f",$_[0];
}
print round(8.7385, 2); # prints 8.74

##</code><code>##

for my $i (0 .. 10)
 {
 print round($i+0.555,2),"  ";
 }
# which prints:
# 0.56  1.56  2.56  3.56  4.55  5.55  6.55  7.55  8.55  9.55  10.56

##</code><code>##

for (my $i = 1; $i < \xFFFF; $i <<= 1)
 { print round($i+0.555,2), "  "; }
# which prints:

#1.56  2.56  4.55  8.55  16.56  32.56  64.56  128.56  256.56  512.55
#1024.56  2048.55  4096.56  8192.56  16384.56  32768.56  65536.55
#131072.55  262144.55  524288.56  1048576.55  2097152.56  4194304.55
#8388608.55  16777216.56
#
#(You can try with different numbers and different precision as long
# as the last digit is '5' and the precision = number of digits - 1)

##</code><code>##

sub round2($$)
{
my $var=$_[0];
my $decimal=($var-int(var));
if ($decimal && ((length($decimal)-2)>$_[1]) && ($var=~/5$/))
 {                                           
 $var=~s/5$/6/;
 }
sprintf "%.$_[1]f",$var;
}

# some output:
for (my $i = 1; $i < \xFFFF; $i <<= 1)
 { print round($i+0.555,2), "  ", round2($i+0.555,2), "\n"; }