Hi Monks, Pls help me locate the reason for the error of the following code, 
#! /usr/bin/perl -w
open AA, '<',"A.txt"    or die "open: $!";
   foreach $line(<AA>)
   {
       chomp($line);
       @temp=split(/\./,$line);
       $new=$temp[0].'.'.$temp[1];
open BB, '<',"B.out"    or die "Failed to open B.out: $!";
       foreach $line1(<BB>)
       {
         @temp1=split(/\s+/,$line1);
         if($new eq $temp1[0])
           {
           print $temp1[1]."\t";
           print $temp1[2]."\n";
           }
       }
close (BB);
}
close(AA);

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Small portions of both the files are as follows, 
A.txt
1a6m_-.ent.dssp
b1b5e_A.ent.dssp
b1bx4_A.ent.dssp
b1bx7_-.ent.dssp
b1bxy_A.ent.dssp

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B.out
b1a6m_-.ent  79K  83E 127.119
b1a6m_-.ent  80G  84A 136.545
b1b5e_A.ent 123R 127M 132.48
b1bx4_A.ent  61H  65S 145.4

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Now, white space b/w column 2 and 3 of B.out is not constant. So while using split in line 11 of my code, I used 
 
 @temp1=split(/\s+/,$line1);

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and got error Use of uninitialized value in string eq at a.pl line 18, <BB> line 427. but if I use 
 @temp1=split(/ +/,$line1);

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it works pretty fine. What is the reason for this err? Isn't / +/ and /\s+/ refer for same thing? Is there a better way of doing this?

In reply to "Err:Use of uninitialized value in string eq" while using split by cool

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