Look at your sort criteria: { $b->[$col_2sort] <=> $a->[$col_2sort] }. $col_2sort is 2, but that array element does not exist. Change the sort criteria to { $b->[1] <=> $a->[1] } and it works.

You really should be using strict and warnings, using them will help clean up your code.

column #2 is (4,9) and looks to already be sorted correctly

Off by one - index 2 is the third column, (5,10). Also the OP appears to want a reverse sort - at least I'm assuming that based on the $b being before $a and the OP saying the current code doesn't work.

>Trying to create a Subroutine to sort array based on any column numerically when my array is having both characters and numercis

I am not sure I completely understand the example...but this will sort alpha and numeric

#! /usr/local/bin/perl -w

use strict;

my $data = [qw| z x y 2 1 3 |];

print 'no sort:' , @$data ,"\n";
print 'sort:   ' , (sort _sort_a_tron @$data) , "\n";

sub _sort_a_tron {  
  
  no warnings; 
  return ( $a <=> $b or $a cmp $b );   
  
} 

# output #
# no sort:zxy213
# sort:   xyz123
[download]

This is basically one of the solutions I offered above, but with a number of caveats about the data.

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
[download]

I want to create a subroutine which takes two argument as input, First argument is array and second argument is column number on which sorting has to be done. Say for example sort_array is a subroutine and I pass OBJD array and column to sort as arguments. something like sort_array(\@OBJD,2) and this should provide me below output

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
[download]

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
[download]

Would like to do it using regular sorting method as well as using 'Schwartzian transform' just to learn it.

Yes, it seems important, if I understand correctly this OP' quote: "my array is having both characters and numercis".

I can see two ways to go about it. Presumably, when using this function, the user knows what there will be in the column, so that the type of comparison could a parameter passed to the function. Assuming this is Boolean parameter stored in the $numeric variable, it could lead to something like this (untested):

    @sorted_array=  map { $_->[0] } 
                    sort { $numeric ? $b->[1] <=> $a->[1] : $b->[1] cm
+p $a->[1]} 
                    map { [ $_, (split " ", $_)[$col_2sort] } @unsorte
+d_array;
[download]

The other way might possibly look simpler (but is probably less clean and more error-prone):

    @sorted_array=  map { $_->[0] } 
                    sort { $b->[1] <=> $a->[1] ||  $b->[1] cmp $a->[1]
+} 
                    map { [ $_, (split " ", $_)[$col_2sort] } @unsorte
+d_array;
[download]

This is based on the idea that comparing two strings with <=> will yield 0, a false result, so that, if we have strings, the cmp comparison will be executed and return the correct comparison. But there are at least two downsides with this approach:

1. You need to silence out the Argument "foo" isn't numeric in numeric comparison (<=>) at ... warning with the appropriate pragma, and I usually hesitate quite a bit before deciding to silence out any warning (except perhaps, but only very very rarely, the initialized and the deep recursion warnings when I really know for sure it is OK);

2. There are several edge cases where it might break, especially if you have one numeric argument and one non-numeric argument:

$ perl -e 'print 3 <=> "b"'
1
 ~
$ perl -e 'print 3 cmp "b"'
-1
[download]

So this could work out for a one-off sort if you know your data very well, but this is really not very robust production code.

Update: Corrected two stupid typos in my code, thanks to AnomalousMonk for proofreading.

What on earth are you talking about? What does cmp have anything to do with the question?

Maybe applicable

No, it's not, as OP is only working with numbers (in the Perl sense), not strings.

Ack, apologies, I spent too much time looking at the code and not enough reading the question. (In my defense, the OP's sample data isn't really representative then :-) )