$num = sprintf "%8g", $num;

  # Format number with up to 8 leading zeroes
  $result = sprintf("%08d", $number);
[download]

Sorry to be dim but with the following lines of code: $_ = FormatSigFigs($_,8); my $clem = sprintf("%08g", $_); print "$clem\n"; and starting with the number 1298.844667, I get the result 01298.84 and not 1298.845, as desired. Any ideas? Thanks again for your help.

Sorry to be a bit dim but, with the following lines of code:

  $_ = FormatSigFigs($_,8);
  my $clem = sprintf("%08g", $_);
  print "$clem\n";
[download]

and the number 1298.844667 as input, I get the output 01298.84 and not 1298.845, which is what I want.
Any ideas?
Thanks again for your help.

Edit: larsen. Added <code> tags and some minor formatting.

In that case, to a first approximation you could do something like the following:

#! /usr/bin/perl -w

use strict;

while( <DATA> ) {
    chomp;

    my $nr = squeeze($_);
    print "[$nr] $_\n";
}

sub squeeze {
  my $n = sprintf( '%0.8f', $_[0] );
  $n =~ s/^0//;
  substr( $n, 0, 8 );
}

__DATA__
12345678901234567890
1234567890
1234567.0
1234567.9
123456.789012345
12345
123.4567
123.4
.1
.1234567890
0.00000999999
[download]

Then again, the few test cases here reveal a certain number of bugs. I contend that the results to squeeze() contain a bug, in that 1234567.0 and 1234567.9 return the same results, but in truth the latter should return 1234568. I don't know whether you will hit these borderline cases or not.

Maybe there's yet another module that deals with your problem.

<update>In response to gjb's remark about whether this code is a good idea or not, I was trying to point out the folly of storing numbers in fixed-width fields. The idea being that when you see what this outputs, maybe you better start thinking about overflow conditions. As I don't know the domain. I can't really deal with in a satisfactory matter (at least to my standards). I prefer to let the code stand as it is.</update>

I don't really think that this piece of code is such a good idea: representing 12345678901234567890 as 12345678 doesn't make sense in any situation I can think of.

I'd suggest the author to check what he's written and either to modify or motivate this program.

Update: Fair enough given the update grinder added.

Just my 2 cents, -gjb-

my $num = 12345.678; # a total of 9 characters
if (length $num > 8)
{
    if ($num =~ /\./) # If there's a decimal point
    {
        # Put it to seven significant figures
    }
    else
    {
        # Put it to eight significant figures
    }
}
[download]

------
We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

What about a minus/plus sign in front of the number? And what if the number is longer than 8 characters, like 1234567890?

I think there are a lot of corner cases lurking around in this problem ... :)

-- Hofmator