you are looking for wisdom, not for elegance! ;=)

Elegance can be your enemy: better looking for efficiency and readability.

You already received a wise answer by Eily++ about grep

If your do_something is short as print you can consider also the unless postscript form:

foreach my $ele (@SlectedColumns[1..$NrCoumns]) {
        
       do_something unless $ele == 0;
}
[download]

It's an handy and readable syntax.

If the loop is complex and actions are more, something very similar to your example is a wise form to express some logic: a good principle exit loop early

foreach my $ele(@SlectedColumns[1..$NrCoumns]) {
     # exit soon
     next if $ele == 0;
     next unless defined $ele;
     ....        

    }
[download]

L*