Comparing arrays with text contents

rsriram has asked for the wisdom of the Perl Monks concerning the following question:

I need to compare two arrays:

@anc=("BX1.01.001","BX1.01.002","BX1.01.003","BX1.01.004","BX1.01.005"
+,"BX1.01.006");
@ind=("BX1.01.002","BX1.01.002","BX1.01.003","BX1.01.004","BX1.01.005"
+,"BX1.01.006");
[download]

My function to compare these two array's is

sub comp_arr
{
    @arr1=sort($_[0]);
    @arr2=sort($_[1]);

    # To check if the number of elements in both arrays match
    if ($#arr1 != $#arr2)
    {
        print "Indicator and anchor count do not match";
        exit;
    }
    
    #Actual compare starts here
    for ($x=0; $x <= $#arr2; $x++)
    {
        if ($arr2[$x] ne $arr1[$x])
        {
        print ("Anchor/indicator mismatch in $arr1[$x]\n");
        }
    }
[download]

Even if the arrays are similar or if there are any differences, I get an error message stating there is a mismatch in the first element. Can someone help me out by telling me what's wrong in the above codes?

Sriram

proper code tags by holli

Comment on Comparing arrays with text contents Select or Download Code

Replies are listed 'Best First'.
Re: Comparing arrays with text contents by Zaxo (Archbishop) on Jun 21, 2006 at 10:53 UTC
Your, `@arr1=sort($_[0]); @arr2=sort($_[1]);` [download] puts exactly one element in each array, a reference to the corresponding array. They will never match unless you compare an array to itself. You want, `my @arr1 = sort @{$_[0]}; my @arr2 = sort @{$_[1]};` [download] Your for loop is more perlishly written, `for (0 .. $#arr1) { if ($arr2[$_] ne $arr1[$_]) { print "Anchor/indicator mismatch in $arr1[$_]\n"; } }` [download] but what you have will work fine. You might be interested in the Algorithm::Diff package. After Compline, Zaxo	[reply] [d/l] [select]
Re: Comparing arrays with text contents by Samy_rio (Vicar) on Jun 21, 2006 at 11:00 UTC
Hi, Try this using `Array::Compare` module. TIMTOWTDI `use strict; use warnings; use Array::Compare; my @anc=("BX1.01.001","BX1.01.002","BX1.01.003","BX1.01.004","BX1.01. +005","BX1.01.006"); my @ind=("BX1.01.002","BX1.01.002","BX1.01.003","BX1.01.004","BX1.01. +005","BX1.01.006"); my $comp = Array::Compare->new(); if (!($comp->compare_len(\@anc, \@ind))){ print "Indicator and anchor count do not match"; exit; } if ($comp->compare(\@anc, \@ind)){ print "Same Array OK"; }else{ print "Different Array OK"; }` [download] Use `$comp->perm(\@anc, \@ind)` for compare the array without order. Regards, Velusamy R. eval"print uc\"\\c$_\""for split'','j)@,/6%@0%2,`e@3!-9v2)/@\|6%,53!-9@2~j';	[reply] [d/l] [select]
Re: Comparing arrays with text contents by mickeyn (Priest) on Jun 21, 2006 at 10:55 UTC
Check Array::Compare Enjoy, Mickey	[reply]
Re: Comparing arrays with text contents by prasadbabu (Prior) on Jun 21, 2006 at 10:56 UTC
The following code works for me. You are using sort function wrongly as Zaxo indicated. Also i think you are not sending the arrays as reference for subroutine parameters. You have to send the arrays as reference for subroutine parameters. For example, `comp_arr (\@anc, \@ind)` use strict; use warnings; my @anc=("BX1.01.001","BX1.01.002","BX1.01.003","BX1.01.004","BX1.01.0 +05","BX1.01.006"); my @ind=("BX1.01.002","BX1.01.002","BX1.01.003","BX1.01.004","BX1.01.0 +05","BX1.01.006"); comp_arr (\@anc, \@ind); sub comp_arr { my @arr1= sort (@{$_[0]}); my @arr2= sort (@{$_[1]}); if ($#arr1 != $#arr2) { print "Indicator and anchor count do not match"; exit; } for my $x (0..$#arr2) { print "$arr1[$x]\t$arr2[$x]\n"; print ("Anchor/indicator mismatch in $arr1[$x]\n") if ($arr2[$ +x] ne $arr1[$x]); } } output: ------- BX1.01.001 BX1.01.002 Anchor/indicator mismatch in BX1.01.001 BX1.01.002 BX1.01.002 BX1.01.003 BX1.01.003 BX1.01.004 BX1.01.004 BX1.01.005 BX1.01.005 BX1.01.006 BX1.01.006 [download] Prasad	[reply] [d/l] [select]
Re: Comparing arrays with text contents by Moron (Curate) on Jun 21, 2006 at 11:38 UTC
`( $#ar1 == $#ar2 ) and ( $ar1[$_] eq $ar2[$_] ) \|\| 0 \|\| last for ( 0 .. $#ar1 );` [download] -M Free your mind	[reply] [d/l]


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