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
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.