The OP doesn't say that so I assume that you know them personally?
In the level of thread that I directly replied to, the Original Poster says: "I am a PhD genome biologist still getting to grips with the finer details of Perl".

The OP says they have "an array with 5 elements" but you chose to store that in a string and then split it.
Well, I certainly did focus on the OP's description of the output: 
one two three four five
row_1 = 1 1 0 0 1
row_2 = 0 1 0 1 0
row_3 = 1 0 1 1 1
etc...

[download]
It looked to me like there would be line with the column names - I certainly was thinking about a normal CSV type header. If not so what? We are focusing on the wrong detail.

I think we are getting bogged down into small details... You posted an excellent solution as did I. Let's leave it at that.

In reply to Re^7: making presence/absence table from a hash of arrays by Marshall
in thread making presence/absence table from a hash of arrays 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.