my %hash = ();
my $line = "";

[download]

What do those two mean?? why do people do this?

Update

sub readfasta {
  my $ifn = shift;
  my $IFH;
  open($IFH, "<$ifn") or die "cannot open file $ifn\n";
  my $line;
  my %ret;
  my $tot = 0;
  while($line = <$IFH> ){
    chomp $line;
    if(not($line eq "")) { ##### why does $line equal "" ?
      my @tmp = split(//,$line);
      if($tmp[0] eq ">") {
        my $nm = substr($line,1);
        $nm = $nm . $tot;
        $tot++;
        $line = <$IFH>;
        chomp $line;
        $ret{$nm} = $line;
      }
    }
  }
  close($IFH);
  return(\%ret);
}

[download]

what does $line = ""; mean?

In reply to need a clearer understanding by DanielM0412

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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