Declare hash variable in loop - perl

Question

I need to use a hash and loop in my code. Please see the sample code it's not working. i wanted to print the variable wafer, site and res side by side so it will look like this
1, 1, 63
1, 2, -53
1, 3, 9.47
1, 4, 9.55
1, 5, -8.32
my #wafer = ("1","1","1","1","1");
my #site = ("1", "2", "3", "4", "5");
my #res = ("63","-53","9.47","9.55","-8.32");
my %hash;
foreach my $result(#res) {
$hash{$wafer[0]}{$site[0]} = $result;
last;
}
print "$wafer{$wafer[0]}{$site[0]} \n";

Answer 1

When you want to iterate several arrays synchronously, iterate over the indices:
for my $index (0 .. $#wafer) {
print "$wafer[$index] $site[$index] $res[$index]\n";
}
You also might want to build a hash keyed by the site (as it's the only unique value):
for my $index (0 .. $#wafer) {
$hash{ $site[$index] } = { wafer => $wafer[$index],
res => $res[$index] };
}
This will create a hash like this:
%hash = (
'4' => {
'res' => '9.55',
'wafer' => '1'
},
'3' => {
'wafer' => '1',
'res' => '9.47'
},
'1' => {
'res' => '63',
'wafer' => '1'
},
'2' => {
'res' => '-53',
'wafer' => '1'
},
'5' => {
'res' => '-8.32',
'wafer' => '1'
}
);