Picture fields that begin with ^ rather than @ are treated
       specially.  With a # field, the field is blanked out if
       the value is undefined.  For other field types, the caret
       enables a kind of fill mode.

##</code><code>##

{ no warnings;
format STDOUT =
@<<<<<<<<<<<<<   ^####   @#####.##
$output[$i], $output[$i+1], $output[$i+2]/1024
.
}