Question

I am trying to create an array of hashes, and I am wondering how to reference each hash within the array?

For eg:

while(<INFILE>)    
{    
  my $row = $_;    
  chomp $row;    
  my @cols = split(/\t/,$row);    
  my $key = $cols[0]."\t".$cols[1];     

  my @total = (); ## This is my array of hashes - wrong syntax???    

  for($i=2;$i<@cols;$i++)    
  {    
    $total[$c++]{$key} += $cols[$i];      
  }    
}

close INFILE;

foreach (sort keys %total)  #sort keys for one of the hashes within the array - wrong syntax???    
{    
  print $_."\t".$total[0]{$_}."\n";    
}

Thanks in advance for any help.

Answer 1

You don’t need

my @total = ();

This:

my @total;

is sufficient for what you are after. No special syntax needed to declare that your array will contain hashes.

There’s probably different ways of doing the foreach part, but this should work:

foreach (sort keys %{$total[$the_index_you_want]}) {
  print $_."\t".$total[$the_index_you_want]{$_}."\n";
}

[BTW, declaring my @total; inside that loop is probably not what you want (it would be reset on each line). Move that outside the first loop.]

And use strict; use warnings;, obviously 🙂