I'm attempting to store hash names in an array and then interpolate them in a loop. Is this even possible? My data is an array with the data arranged in groups for each value.

So $a{1}=5.5, $a{2}=3.2, $b{1}=15.0, $b{2}=-22, $c{1}=.02 and $c{2}=.15.

Here's what I'm attempting to do: 

my @fields = qw(a b c);
my @input = qw( 5.5 3.2 15.0 -22 .02 .15);

for ($i=0; $i<=2; $i++) {
   for ($j=1; $j<=2; $j++) {
      $${fields[$i]}{$j} = $input[((2*$i)+$j)-1];
   }
}

for ($i=0; $i<=2; $i++) {
   for ($j=1; $j<=2; $j++) {
      print $fields[$i] . "{" . $j . "} -> " . $${fields[$i]}{$j}, "\n
+";
   }
}

printf "%.1f\t%.1f\t%.1f\n", $a{1}, $b{1}, $c{1};

[download]

The data gets entered into the hashes, though I'm not so sure now. If I run it, it prints the for loop correctly. This croaks when it gets to the printf line with a couple of "uninitialed value" warnings and prints out zeros.

Can I use the hashes by name? Do they only exist elements of the array they're in? Do I need to do my homework and look up references? I was hoping to be clever and get my way out of that (being inexperienced and all...)

Thanks for any answers

- chris

In reply to Interpolating an array element as a hash name. by yam

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