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

Hello again,
I'm using the following code to try and print the data from the following dump without success. 
$VAR1 = {
  'request_1.3.6.1.2.1.2.2.1.12.30' => {
    'Error_Status' => 'No error',
    '1.3.6.1.2.1.2.2.1.19.30' => [
      [
        'ifOutDiscards.30',
        '6'
      ]
    ],
    '1.3.6.1.2.1.2.2.1.11.30' => [
      [
        'ifInUcastPkts.30',
        '6'
      ]
    ],
    '1.3.6.1.2.1.2.2.1.20.30' => [
      [
        'ifOutErrors.30',
        '6'
      ]

while ( my ($key, $reference) = each %key_hash){
    foreach my $temp (@{$reference}){
        print "$key, $reference\n";
    }
}

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It's returning: 
request_1.3.6.1.2.1.2.2.1.12.30, HASH(0x1e111cc)

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Anyone see my mistake?

Replies are listed 'Best First'.
Re: Printing a hash of arrays ??
by Mr. Muskrat (Canon) on Mar 26, 2003 at 21:59 UTC

    Yeah. Two things.

    1. You still haven't signed up for an account. ;-)
    2. while ( my ($key, $reference) = each %key_hash){
    foreach my $temp (@{$reference}){
        print "$key, $reference\n";
    }
}

      [download]
      You loop through @{$reference} assigning the values to $temp but you never use it. Instead you print $key and $reference.

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      lol....no I haven't but I will. This is a great site, and everyone has been so helpful.
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Re: Printing a hash of arrays ??
by chromatic (Archbishop) on Mar 26, 2003 at 21:54 UTC

    Try printing $temp instead of $reference.

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Re: Printing a hash of arrays ??
by dragonchild (Archbishop) on Mar 27, 2003 at 00:10 UTC
    First off, that code isn't making that result. You can't treat a hash reference like an array reference. :-)

    Secondly, you need to iterate an additional level. I'm seeing you make this mistake (or some variant thereof) in every post you've made. You're trying the first time, maybe trying again, then giving up. You really need to think through what you're doing. If you haven't already, I would suggest hand-tracing your program, writing up the data structures on a whiteboard (or somesuch), and seeing how the program moves through the data structure.

    In all programs, and especially yours, the data structure is king. The code only walks around within it, grabbing stuff as it needs. You haven't fully learned your data structure, so you have no idea how to work with it. I and a coworker once spent over a week working on the data structure for one function. Most of that was spent in front of a whiteboard, not a computer.

    The point is that time spent coding when you don't understand the problem domain or how you're going to represent it is time wasted - pure and simple. In fact, it's worse than time wasted because you're going to keep the dreck that you came up with during that wasted time. This is despite the fact that you would save time by throwing away what you had and starting from scratch.

    ------
    We are the carpenters and bricklayers of the Information Age.

    Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

    Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.

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      At times like this I am thankful for Data::Dumper.
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        OK, I'm still confused...lol (I've created a data structure that I can't retrieve info from
        I've revised my code to the following: 
        foreach $key (keys %key_hash) {
    print "KEY: $key\n";
    print "MIN_TIME_DIFF: $key_hash{$key}{Min_Time_Diff}\n";
    print "MAX_TIME_DIFF: $key_hash{$key}{Max_Time_Diff}\n";
    print "ERROR STATUS: $key_hash{$key}{Error_Status}\n";
    foreach my $value (%{$key_hash{$key}}) {
    print "VALUE: $value\n";
    }
}

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        All I want to do is extract the two array elements from each key in the hash of hashes
        My code is returning the following: 
        KEY: response_1.3.6.1.2.1.2.2.1.12.27
MIN_TIME_DIFF: 1:00:00.0000
MAX_TIME_DIFF: 1:00:00.0000
ERROR STATUS: No error
VALUE: 1.3.6.1.2.1.2.2.1.15.28
VALUE: ARRAY(0x1e47028)
VALUE: 1.3.6.1.2.1.2.2.1.15.27
VALUE: ARRAY(0x1e49fc8)
VALUE: 1.3.6.1.2.1.2.2.1.11.27
VALUE: ARRAY(0x1e49fd8)

        [download]
        What am I doing wrong?
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