-59.077    89.301   115.664       7
-61.251    77.435   117.760      -6
-60.950    71.712   116.061      -7
-56.247    83.685   114.576       1
-59.263    76.107   112.555      -2
-59.895    65.296   111.185       3
-60.141    63.694   111.257      -3
-61.667    63.707   116.937       2
-58.722    60.429   111.307      -1 
-57.511    42.922   112.108       6

##</code><code>##

 7   -59.077    89.301   115.664
-7   -60.950    71.712   116.061

##</code><code>##

 -6  -61.251    77.435   117.760  
  6  -57.511    42.922   112.108 
##</code><code>##

-1   -58.722    60.429   111.307
 1   -56.247    83.685   114.576
##</code><code>##

 7   1   -59.077    89.301   115.664
-7   3   -60.950    71.712   116.061
##</code><code>##

-6   2  -61.251    77.435   117.760  
 6  10  -57.511    42.922   112.108 
##</code><code>##

-1   9   -58.722    60.429   111.307
 1   4   -56.247    83.685   114.576
##</code><code>##

#!/usr/bin/perl
use warnings;
use strict;

open my $target, '>', "test-out-1" or die $!;

open my $FILE, '<', 'input_file' or die $!;
while (<$FILE>) {

  chomp;
  my @columns = unpack('a8 a8 a8 a6');
  #print join(" ",map {$_} @columns), "\n";
  #print "@columns[3] \n";
    
  foreach (@columns[$#columns]) {
   print "$_ \n";
      if ($_ =~ /-7/) {
     
      my $ID = $_;
      my $IDform = sprintf ("%4s", $ID);
      
      my $currentline = $.;
      my $currentlineform = sprintf ("%7s", $currentline);

      my @selection = (@columns[0..$#columns-1]);
      my $layout = "%10s"x(@selection) . "\n";
      printf $target $IDform . $currentlineform . $layout, @selection;
      }
  }
}
##</code><code>##

   -7    418   -17.459    -3.557   123.002
   -7    419   -19.119    -2.327   121.948
   -7    421   -18.172    -5.439   122.677
   -7    423   -21.239    -5.003   128.245
   -7    424   -17.575    -3.567   124.891
   -7    425   -19.519     1.088   136.199
   -7    426   -17.135    -5.042   124.510
   -7    427   -19.539    -2.356   127.619
   -7    429   -16.867     0.671   123.725
   -7    430   -19.638     8.992   126.487
   -7    431   -19.731    13.090   129.183
   -7    432   -17.846    15.834   128.342
   -7    440   -20.265    16.101   127.072

##</code><code>##

#!/usr/bin/perl
use warnings;
use strict;

my $match;
my @match = ();

push (@match, $match); # I fear this is what I'm doing wrong - I'm not putting $match in @match correctly. 

@match = (-10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10);

my $value = abs($match); # Here I'm trying to establish a variable that will basically be the absolute value of the fourth column of my input file, this is what I want to match.

open my $target, '>', "test-out-$value" or die $!;

open my $FILE, '<', 'input_file' or die $!;
while (<$FILE>) {

  chomp;
  my @columns = unpack('a8 a8 a8 a6');
  #print join(" ",map {$_} @columns), "\n";
  #print "@columns[3] \n";
    
  foreach (@columns[$#columns]) {

      if ($_ =~ /$value/) {
     
      my $ID = $_; 
      my $IDform = sprintf ("%4s", $ID); # Also here I'm confused and I can't think about how to write what I want. I want to match the absolute value (a few lines above), but print the actual value (in my output file), not the absolute one. This worked easily in my first code (where I matched for specific number) but now I can't think how to write the general version.
     
      my $currentline = $.;
      my $currentlineform = sprintf ("%7s", $currentline);##

      my @selection = (@columns[0..$#columns-1]);
      my $layout = "%10s"x(@selection) . "\n";
      printf $target $IDform . $currentlineform . $layout, @selection;
     }
  }
}