my @fieldnames = qw /S_10 S_11 S_12 S_13 S_14 S_15 T_10 T_11 T_12 T_13 T_14 T_15/;
     # Note you could also make it dynamic and generate it from the input
my %params;
while (<$Param>) {
     my ($index, @values) = split /,/, $_;
     $params{$index} = { map {$fieldnames[$_], $values{$_}} 0..15;}
}