>perl -wMstrict -le
"my @COUNT = (
   'Family    lacM    taba    mori    glyB    gly4',
   'OG_1    1    0    1    0    0',
   'OG_2    0    1    0    1    0',
   );
 ;;
 my @families = split /\s+/, shift @COUNT;
 ;;
 my %participants;
 for my $record (@COUNT) {
   my @fields = split /\s+/, $record;
   $participants{$fields[0]} =
     [ map { $families[$_] } grep { $fields[$_] } 1 .. $#fields ];
   }
 ;;
 use Data::Dumper;
 print Dumper \%participants;
"
$VAR1 = {
          'OG_2' => [
                      'taba',
                      'glyB'
                    ],
          'OG_1' => [
                      'lacM',
                      'mori'
                    ]
        };

[download]

Update: The expression
    [ map { $families[$_] } grep { $fields[$_] } 1 .. $#fields ]
is more concise and perhaps a bit faster as
    [ map $families[$_], grep $fields[$_], 1 .. $#fields ]

In reply to Re: Getting indices of the same value that occurs multiple times in an array... by AnomalousMonk
in thread Getting indices of the same value that occurs multiple times in an array... by reubs85

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.