Re: hashes - finding values

Because exists checks for the existence of keys and not values. Instead a grep might be better suited e.g

my @array = qw/ foo bar baz quux /;
my %hash  = qw/ f1  baz f2  foo  /;
my @newarray;

foreach my $thing (@array)   {
   push @newarray, $thing
     if grep { $_ eq $thing } values %hash;
}

print "newarray - @newarray\n";

__output__

newarray - foo baz
[download]

This isn't terrifically optimal so you may want to create another hash where the values are the keys (although the solution starts to look like finding an array intersection which is another option).
HTH

_________ broquaint

Comment on Re: hashes - finding values Download Code

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Re: Re: hashes - finding values by Anonymous Monk on Jul 03, 2003 at 13:45 UTC
Thanks broquaint but I want to push the corresponding keys to the matching values into the new array. I think your code keeps values in the array that are present in the hash. `my @array = qw/ f1 f2 f3 f4/; my %hash = qw/ f1 foo f2 bar/; #OUTPUT # newarray - foo bar.` [download] I'm not too sure how to adapt your code to do this!	[reply] [d/l]
Re: Re: Re: hashes - finding values by broquaint (Abbot) on Jul 03, 2003 at 13:50 UTC
Ok, then you'll want something like ... `my @array = qw/ foo bar baz quux /; my %hash = qw/ f1 baz f2 foo /; my @newarray; for my $k (keys %hash) { push @newarray, $k if grep { $hash{$k} eq $_ } @array; } print "newarray - @newarray\n"; __output__ newarray - f1 f2` [download] HTH `_________ broquaint`	[reply] [d/l]