How do I access array of hash in perl?
arrays, hash, perl, push
Solution
First you should
use strict;
use warnings;
then define
my $my_hash;
initialize `$my_hash` before you assign values, because otherwise you overwrite it and all three elements point to the same hash
$my_hash = {};
and finally, to access the hash's members
$myarray[$i]->{firstname}
or to print the whole hash, you can use Data::Dumper for example
print Dumper($myarray[$i])."\n";
or some other method, How can I print the contents of a hash in Perl? or How do I print a hash structure in Perl?
Update to your comment:
You copy the hashes with
push (@modifymyhash, $myarray[$i]);
into the new array, which works perfectly. You can verify with
foreach my $h (@myarray) {
print Dumper($h), "\n";
}
foreach my $h (@modifymyhash) {
print Dumper($h), "\n";
}
that both arrays have the same hashes.
If you want to make a deep copy, instead of just the references, you can allocate a new hash and copy the `ith` element into the copy. Then store the copy in `@modifymyhash`
my $copy = {};
%{$copy} = %{$myarray[$i]};
push (@modifymyhash, $copy);
Problem
I have a big array of hashes, I want to grab some hash from the array and insert into new array without changing the first array. I am having problem pushing the hash to array, how do I access the ith element which is a hash. ``` my @myarray; $my_hash->{firstname} = "firstname"; $my_hash->{lastname} = "lastname"; $my_hash->{age} = "25"; $my_hash->{location} = "WI"; push @myarray,$my_hash; $my_hash->{firstname} = "Lily"; $my_hash->{lastname} = "Bily"; $my_hash->{age} = "22"; $my_hash->{location} = "CA"; push @myarray,$my_hash; $my_hash->{firstname} = "something"; $my_hash->{lastname} = "otherthing"; $my_hash->{age} = "22"; $my_hash->{location} = "NY"; push @myarray,$my_hash; my @modifymyhash; for (my $i=0;$i<2; $i++) { print "No ".$i."\n"; push (@modifymyhash, $myarray[$i]); print "".$myarray[$i]."\n"; #How do I print first ith element of array which is hash. } ```