Here's a straightforward solution based on something I used to do on my Commodore 64. :) 

sub roundoff
{
  my $num = shift;
  my $roundto = shift || 1;

  return int($num/$roundto+0.5)*$roundto;
}

foreach my $i (0.6, 1.2, 38.4, 88.6, 92.5)
{
  printf "%5.1f  ",$i;
  foreach my $j (1, 10, 100)
  {
    printf "%2d  ", roundoff($i,$j);
  }
  print "\n";
}

[download]

Update: This actually rounds to the nearest number; I misread the OP's question. Here's a similar solution that always rounds up: 

use POSIX qw(ceil);

sub roundup
{
  my $num = shift;
  my $roundto = shift || 1;

  return int(ceil($num/$roundto))*$roundto;
}

[download]

Another Update: This function will find the right scale according to my understanding of the OPs question. You can use something like roundup($i,rightscale($j)) to get the auto-scaling behavior. 

sub max
{
  return $_[0] > $_[1] ? $_[0] : $_[1];
}

sub rightscale
{
  my $num = shift;
  return 10 ** max(int(log(abs($num))/log(10))-1,1);
}

[download]

In reply to Re: Rounding up nearest ten, hundred etc by sgifford
in thread Rounding up nearest ten, hundred etc by nite_man

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