Perl Compare 2 Arrays

Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Perl Compare 2 Arrays
# 1  
Old 01-03-2011
Perl Compare 2 Arrays


Consider the following 2 arrays:
Array1 = qw(Fa0/0 Fa0/1 Fa0/2 Fa0/3);
Array1 = qw(Fa0/1 Fa0/2 Fa0/3 Fa0/4);

I want to compare the following 2 arrays as follows:
  • Take specific action when elements of Array1 that doesn't exist in Array2 (in my example: Fa0/0).
  • Take another action when elements of Array2 that doesn't exist in Array1 (in my example: Fa0/4).
please advise.
# 2  
Old 01-03-2011
# That can be done by hashes concept
@Array1 = qw(Fa0/0 Fa0/1 Fa0/2 Fa0/3);
@Array2 = qw(Fa0/1 Fa0/2 Fa0/3 Fa0/4);
# process two array , increment the values and store into hash
$hash{$_}++ for (@Array1, @Array2);
for (keys %hash)
 # print the value equal to one 
 print "\n$_" if ($hash{$_} == 1);

For more details go to command mode and process the below command
perldoc -q unique

Last edited by k_manimuthu; 01-03-2011 at 06:20 AM.. Reason: More information
This User Gave Thanks to k_manimuthu For This Post:
# 3  
Old 01-03-2011

Many thanks for your support.

It works well and I got the both Fa0/0 and Fa0/4.

but as I mentioned first, I want to run a differnt actions for both output (action if element in array1 doesn't exist in array2 and different action if element in array2 doesn't exist in array1).

Also it doesn't work properly when the array has duplicate values (this possible in my case).

Appreaciate your reply.

# 4  
Old 01-03-2011
# Declare your array's
@Array1 = qw(Fa0/0 Fa0/1 Fa0/2 Fa0/3);
@Array2 = qw(Fa0/1 Fa0/2 Fa0/3 Fa0/4);
# compare array1 elements to array2 elements
foreach $key1 ( @Array1)
 $flag=0; # set the flage value
 foreach $key2 ( @Array2)
  if ($key1 eq $key2)
 # that considered array 1 element doesn't match array2 elements
 if ($flag == 0 ) 
  print "\nValue '$key1' doesn't exist in \@Array2";
  ## Do your actions here
# use the above logic and compare array2 to array1
# Your stuff's Here

# 5  
Old 01-03-2011

See also the module:
       List::Compare - Compare elements of two or more lists

       This document refers to version 0.37 of List::Compare.  This version
       was released June 07, 2008.

       The bare essentials:

           @Llist = qw(abel abel baker camera delta edward fargo golfer);
           @Rlist = qw(baker camera delta delta edward fargo golfer hilton);

           $lc = List::Compare->new(\@Llist, \@Rlist);

           @intersection = $lc->get_intersection;
           @union = $lc->get_union;

       ... and so forth.

-- excerpt from perldoc List::Compare, q.v.

Depending on your system, you may need to install List::Compare ... cheers, drl
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

Compare bash arrays issue

Hello everyone, I need help comparing 2 arrays. the first array is static; the second array is not .. array1=( "macOS Mojave" "iTunes" ) cd /Volumes array2=( * ) # output of array2 macOS Mojave iTunes Mac me The problem occurs when I compare the arrays with the following code - ... (6 Replies)
Discussion started by: trexthurman
6 Replies

2. Shell Programming and Scripting

Using Diff to compare 2 arrays

I have two arrays and they look like this: array=(`cat /local/mnt/*sys/*includes|grep -v NEW`) array2=(`cat /tmp/*sys.z |grep -v NEW`) I am trying to compare them but I need to use the diff -u command. I am not sure how to do this. I cannot just do diff -u ${array} ${array2} I cannot... (4 Replies)
Discussion started by: newbie2010
4 Replies

3. Shell Programming and Scripting

Compare two arrays

Hi, I am trying to compare two lists that are held in two variables so I believe I need to access the array elements to compare these. I am using ksh 88 and the code I have tried is below: for file in ${origfilelist} do if ]] then print -- "File ${file}... (3 Replies)
Discussion started by: frodo61
3 Replies

4. Shell Programming and Scripting

perl: compare two arrays

Hi friends, I want to compare two arrays and find matched one using perl? Also, I want to delete unmatched one. Plz suggest me solution (1 Reply)
Discussion started by: Renesh
1 Replies

5. Shell Programming and Scripting

Compare arrays (perl)

Hi, my first post here! Description of my problem: I have one txt-file with six rows and each row contains seven numbers seperated with whitespaces. I want to: Compare one array with seven numbers with each row of numbers in the txt-file. I have managed to compare one array with... (6 Replies)
Discussion started by: mjoh
6 Replies

6. Shell Programming and Scripting

compare 2 arrays in perl

Hi Im supposed to compare lines in a file : KB0005 1019 T IFVATVPVI 0.691 PKC YES KB0005 1036 T YFLQTSQQL 0.785 PKC YES KB0005 1037 S FLQTSQQLK 0.585 DNAPK YES KB0005 1045 S KQLESEGRS 0.669 PKC YES KB0005 1045 S KQLESEGRS 0.880 unsp YES KB204320 1019 T IFVATVPVI 0.699 PKC YES ... (7 Replies)
Discussion started by: karla
7 Replies

7. Shell Programming and Scripting

Compare arrays in perl

Hello, Let's say that we have the two following arrays @array1= @array2= Is there any easy way to compare these two arrays and print the values that exist in array1 and not in array2 and the values that exist in array2 and not in array1? Regards, Chriss_58 (3 Replies)
Discussion started by: chriss_58
3 Replies

8. Shell Programming and Scripting

compare/match arrays

Hi there all, I am having a question. Is it posible to compare elements of 2 different arrays? For example I got Array 1 | Array 2 123_abc | 123_bcd 123_bcd | 234_bcd 234_abc | 567_abc 234_bcd | 123_abc than the match is 123_abc & 234_bcd and non of the others. So... (3 Replies)
Discussion started by: draco
3 Replies

9. Shell Programming and Scripting

Perl - Compare 2 Arrays

Hi all, I have the following script where the contents of file1 and file2 would be something like this: file1: 56790,0,0,100998765 89756,0,0,100567876 867645,1,3,678777654 file2: 56790,0,0,100998765 65776,0,0,4766457890 +5896,0,0,675489876 What I then want to do is check if... (4 Replies)
Discussion started by: Donkey25
4 Replies

10. Shell Programming and Scripting

Compare two arrays in sh or compare two fields

I want a soultion to compare two arrays in sh with an easy way.I want a solution to synchrose users between different AIX servers where no NIS is available. All users are meant to be same on all 10 servers. So the approach is to consider first server as master user repository and whatever the users... (0 Replies)
Discussion started by: rijeshpp
0 Replies
Login or Register to Ask a Question

Featured Tech Videos