how to assign lines of variable length to a variable in perl? - perl

Question

I have a file I want to read that has a variable number of ids for each location that looks like this:
loc1 id1 id4 id5 id9
loc2 id2
loc3 id1 id11 id23
I would like to store this as follows locs(loc) = {all ids belonging to that location}
So that later, when I read another file I can do something like
if (grep id, locs(loc)){do something}
I tried to do this using a hash, but this is not working. I tried:
open my $loclist, '<', $ARGV[0];
my %locs;
while (<$loclist>) {
my #loclist_rec = split;
my $loclist_loc = #rlist_rec[0];
$locs{$loclist_loc} = #loclist_rec;
}
but this isnt working.
I new to perl and still trying to understand the different datatypes.
Any ideas? Thanks a lot!

Answer 1

This should do what you want.
#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;
open my $loclist, '<', "test.txt" or die $!;
my %locs;
while (<$loclist>) {
my ($loclist_loc, #loclist_rec) = split;
$locs{$loclist_loc} = \#loclist_rec;
}
print Dumper \%locs;
OUTPUT:
$ perl test.pl
$VAR1 = {
'loc2' => [
'id2'
],
'loc1' => [
'id1',
'id4',
'id5',
'id9'
],
'loc3' => [
'id1',
'id11',
'id23'
]
};

Answer 2

Also a possible choice would be a hash of hashes. When you want to look up an id, you could say if ($locs{$loc}{$id}) {do something}. The data structure would be
$VAR1 = {
'loc2' => {
'id2' => 1
},
'loc1' => {
'id1' => 1,
'id5' => 1,
'id4' => 1,
'id9' => 1
},
'loc3' => {
'id1' => 1,
'id11' => 1,
'id23' => 1
}
};