Do I need to do my homework and look up references?

Well, since you're using references already, you might as well go ahead and learn how to use them properly, so that you avoid the evil, insanity-inducing idea of interpolating variable names.

I assume you're showing us a toy example that has very little to do with an application where you believe this problem is coming up. But since you didn't say anything about your real application, let's try to see why you think the following approach poses any sort of problem for the inexperienced programmer: 

my %hash;
my @topkeys = qw/a b c/;
my @innerkeys = qw/1 2/;
my @values = qw/5.5 3.2 15.0 -22 .02 .15/;

for my $k ( @topkeys ) {
    for my $i ( @innerkeys ) {
        $hash{$k}{$i} = shift @values;
    }
}

print join "\t", (map { sprintf("%.1f",$hash{$_}{1}) } qw/a b c/), "\n
+";

# or, if "map" is too tough for the inexperienced:

printf( "%.1f\t", $hash{$_}{1} ) for ( qw/a b c/ );
print "\n";

[download]

In reply to Re: Interpolating an array element as a hash name. by graff
in thread Interpolating an array element as a hash name. by yam

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