Split string into array (uneaven column lengths)
<p>I have a data fine being read in using file() and iterate over each row. Need to be able to split the string into an array of "columns". Problem is the columns are not even widths (60 chars, 40 chars, etc). Seems like all the functions to do this expect that the columns are a fixed size.</p>

<p>This will be performed on a large data file quite regularly so optimal performance is desired. </p>

<p>Example of data.</p>

<pre><code>XXXXXXXXXXXXXXXXXXXXXXXXXX                                  XXXXXXXXXXXXX           XX        XXXXXX
XXXXXXXXX                                                   XXX XXX                 X         XXX
XXXXXXXXXXXXXXX                                             XXXXXXXXXXXXX           XX        XXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXX                                  XXXXXXXXXXXXX           XX        XXXXXX
XXXXXXXXX                                                   XXX XXX                 X         XXX
XXXXXXXXXXXXXXX                                             XXXXXXXXXXXXX           XX        XXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXX                                  XXXXXXXXXXXXX           XX        XXXXXX
XXXXXXXXX                                                   XXX XXX                 X         XXX
XXXXXXXXXXXXXXX                                             XXXXXXXXXXXXX           XX        XXXXXX
</code></pre>
