Counting the elements of a hash of arrays of arrays

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

Oh wise monks,

I have toiled at this question and can't seem to get it.

I have a data structure that's a hash consisting of an array of arrays, created like this:

push @{$results{$addr}},[@output];
[download]

I need to get the count of how many elements are in the lowest level of this structure (that is, how many @outputs are there in the hash $results{$addr}).

I've tried a lot of solutions, and none seem to work. This:

my @a = $results{$addr};
[download]

returns an array with a single element, that then contains all the @output's. But if I try to 'scalar @a' I get '1', and if I scalar @a[0] or scalar($a[0]) I get a bunch of ARRAY refs.

$a = $results{$addr}[0] returns what appears to be an array ref in $a, but scalar(@$a) doesn't return anything, oddly.

No more direct manipulation of $results{$addr} seems to result in anything usable... If I do scalar @$results{$addr} I get 'Variable "$results" is not imported'. If I try print scalar $results{$addr} I get a list of array refs again.

I'm quite frustrated and though I feel I'm missing something simple, I can't figure out what the heck it might be.

All help appreciated.

"Non sequitur. Your facts are un-coordinated." - Nomad

Comment on Counting the elements of a hash of arrays of arrays Select or Download Code

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Re: Counting the elements of a hash of arrays of arrays by broquaint (Abbot) on May 14, 2003 at 18:46 UTC
`my %results = ( addr => [ [ 1 .. 5 ] ] ); print "count is - ", scalar @{ $results{addr}->[0] }; __output__ count is - 5` [download] See. tye's References quick reference and `perlreftut` for more info. HTH `_________ broquaint`	[reply] [d/l]
Re: Re: Counting the elements of a hash of arrays of arrays by Clownburner (Monk) on May 14, 2003 at 19:18 UTC
This just about did it. As it turns out I had to do `scalar @{ $results{$addr} }` to get the count of the @outputs, but it's brilliant. Now why couldn't I think of that? :-P "Non sequitur. Your facts are un-coordinated." - Nomad	[reply] [d/l]
Re: Counting the elements of a hash of arrays of arrays by bigj (Monk) on May 14, 2003 at 18:46 UTC
`my @a = $results{$addr};` [download] returns an array with a single element, that then contains all the @output's. But if I try to 'scalar @a' I get '1', and if I scalar @a[0] or scalar($a[0]) I get a bunch of ARRAY refs. Try instead the same what you you have done to push at the array. `my @a = @{$result{$addr}};` [download] Greetings, Janek	[reply] [d/l] [select]
Re: Counting the elements of a hash of arrays of arrays by artist (Parson) on May 14, 2003 at 18:50 UTC
This small program should help you. Use Data::Dumper when in doubt. `use Data::Dumper; use strict; my @output = (1,2,3); my $addr = 'x'; my %results; push @{$results{$addr}},[@output]; @output = (4,5); $addr = 'y'; push @{$results{$addr}},[@output]; @output = (1,4,7,9,11); $addr = 'x'; push @{$results{$addr}},[@output]; print Dumper(\%results); my $sum; foreach my $addr (keys %results){ my $array_ref = $results{$addr}; foreach my $inner_array_ref (@{$array_ref}){ $sum += scalar @{$inner_array_ref}; } } print $sum;` [download] artist	[reply] [d/l]
Re: Counting the elements of a hash of arrays of arrays by suaveant (Parson) on May 14, 2003 at 18:52 UTC
if you want the number of outputs, you need a loop. `my $count = 0; for(@{$results{$addr}}) { $count += @{$results{$addr}{$_}} } print "$count outputs\n";` [download] untested - Ant - Some of my best work - (1 2 3)	[reply] [d/l]