Re^2: how to use the values of the first hash to be the keys for the second hash

thank you so much.

when I tried to print the %newhash:

#!/usr/bin/perl
use warnings;
use strict;

use Data::Dump qw[ pp ];



#subroutine: read in hash tables

my $hash1=shift;
 open (my $fh1, "<",$hash1) or die "$!";  
    my %h1=();
    while (<$fh1>) {
        chomp;
        my ($k1,$v1)=split /\t/;
        $h1{$k1}=$v1;
}

my $hash2=shift;
 open (my $fh2, "<",$hash2) or die "$!";  
    my %h2=();
    while (<$fh2>) {
        chomp;
        my ($k2,$v2)=split /\t/;
        $h2{$k2}=$v2;
}

my %newhash = map {
    $_ => join ',', @h2{ split ',', $h1{ $_ } };
} keys %h1;

while (my ($k, $v) = each %newhash) {
    print $k, "\t@{$newhash{$k}}\n";
}
[download]

it says "Can't use string ("val3") as an ARRAY ref while "strict refs" in use at line 34, <$fh2> line 3.'"

could you explain to me why?,/p>

Comment on Re^2: how to use the values of the first hash to be the keys for the second hash Download Code

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Re^3: how to use the values of the first hash to be the keys for the second hash by BrowserUk (Patriarch) on Sep 07, 2012 at 22:08 UTC
Have you tried dumping the two input hashes after you've populated them? With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. RIP Neil Armstrong	[reply]
Re^4: how to use the values of the first hash to be the keys for the second hash by lrl1997 (Novice) on Sep 10, 2012 at 04:25 UTC
may sounds stupid, but I don't really understand how to "dumping the two input hashes after populated them"	[reply]
Re^5: how to use the values of the first hash to be the keys for the second hash by BrowserUk (Patriarch) on Sep 10, 2012 at 04:47 UTC
You included the `use Data::Dump qw[ pp ];` from my code into yours; but then you threw away the `pp \%newhash;` which I used to produce the output: `C:\test>junk { key1 => "val5,val6,val7,val8,val9", key2 => "val3" }` [download] If, after populating your two hashes: `%h1` & `%h2`, you used the same tool to dump them to the screen before trying to use them: `pp \%h1; pp \%h2;` [download] You could check whether you have populated them correctly. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. RIP Neil Armstrong div	[reply] [d/l] [select]