Sorry for not being clear in requirement. Consider my OBJD Array data is like shown below:

1   ab    2   3   cd   4   5   6   6
9   rc    4   5   ef   6   3   4   1
7   fa    5   2   tg   5   9   9   0
3   bg    3   9   jh   5   2   2   1
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1   ab    2   3   cd   4   5   6   6
3   bg    3   9   jh   5   2   2   1
9   rc    4   5   ef   6   3   4   1
7   fa    5   2   tg   5   9   9   0
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Or something like sort_array(\@OBJD,6) and this should provide me below output

3   bg    3   9   jh   5   2   2   1
9   rc    4   5   ef   6   3   4   1
1   ab    2   3   cd   4   5   6   6
7   fa    5   2   tg   5   9   9   0
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Would like to do it using regular sorting method as well as using 'Schwartzian transform' just to learn it.

It depends on whether your sample data represents an array-of-arrays, with each non-whitespace token as an element of a sub-array, or a single-level array with each line as an element. In the first case, it's fairly simple, something like this:

sub sort_aoa {
  my( $array, $column ) = @_;
  return sort { $a->[$column] cmp $b->[$column] } @$array;
}
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If each element is a whole line, you'll have to split them into words before sorting. This is where a Schwartzian Transform is likely to help the most, but I'll show the basic idea and you can add that:

sub sort_lines_by_column {
  my( $array, $column ) = @_;
  return sort {
    return( (split ' ', $a)[$column] cmp (split ' ', $b)[$column] );
  } @$array;
}
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(Untested. In both cases, replace the 'cmp' comparison with whatever you want.)

Aaron B.
Available for small or large Perl jobs and *nix system administration; see my home node.

Wow, thanks a lot Aaaron !!!

This is not Array of Array, so I used second code what you have provided and it works perfectly fine. But I have few doubts:

1. In split you have specified ' ' which means it will split on single space, but in reality it splits for any number of space.

2. How can I do it using 'Schwartzian transform', I am still novice in perl, please do not mind.

3. How can I have flexibility to pass sorting order Ascending OR Descending to this subroutine. I tried as shown below but its not working.

sub sort_lines_by_column {
  my( $array, $column, $order ) = @_;
  my $ab;
  my $cd;
if ($order eq 'asc') {$ab = "\$a"; $cd = "\$b";} elsif ($order eq 'dsc
+') {$ab = "\$b"; $cd = "\$a";};
  return sort {
    return( (split ' ', $ab)[$column] <=> (split ' ', $cd)[$column] );
  } @$array;
}
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Its giving error "Use of uninitialized value in numeric comparison (<=>)"

Another piece of the puzzle: sort accepts code refs as the sorting function.

my @l = (10, 2, 200, 23, 3, 9, 11, 1);
my $num = sub { $a <=> $b };
my $str = sub { $a cmp $b };
print join(", ", sort $num @l ), "\n";
print join(", ", sort $str @l ), "\n";
__END__
1, 2, 3, 9, 10, 11, 23, 200
1, 10, 11, 2, 200, 23, 3, 9
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The thread linked to by the other anon above contains some ideas. Personally I like Scalar::Util's looks_like_number, since AFAIK that's the same function Perl uses internally. If you know that your columns always contain either numbers xor non-numbers, testing the first value of the column should be enough to determine which comparison to use for that column. If however your columns contain a mix of numbers and non-numbers (e.g. "1 a","foo","3.14","42","b5ar","93b"), you'll have to make a decision on how to sort a column like that.