The things that you want to work point out some muddiness in your understanding of Perl data types. It would be worthwhile for you to train yourself to pay attention to the sigils (type indicators). For example, you wanted to do:

$logtype=@singlefilter[0];
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Obviously, the left side is a scalar variable, while the right side is an array slice. That's not a good match. Just for typing reasons, it would be better to have

$logtype=$singlefilter[0];
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so you're assigning scalar to scalar. Of course, that still won't give you what you want, because you don't want the reference to the array, you want something out of the referenced array:

$logtype = ${$singlefilter}[0];
# is the same as
$logtype = $singlefilter[0]->[0];
# is the same as
$logtype=$singlefilter[0][0];
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But really, you want to assign several pieces out of the referenced array, so you can go back to using an array slice, assigning to a list:

($logtype, $Regex_Event, $Friendly_Output) = @{$singlefilter[0]}[0,1,2
+];
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The usual perldocs are recommended:

perldoc perldata
perldoc perlreftut
perldoc perllol
perldoc perlref
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