title: R: reshape 2 - colsplit not working with a period/fullstop
body: <p>I am trying to use the reshape2 package and the colsplit to separate at the "." pattern in a vector of strings. Usually it is a straightforward function but for some reason it is not working for me today. </p>
  
  <p>If I try to use a different pattern it works fine. I am not exactly sure how the function works but I tried escaping it like you would in regex but that just through up errors although admittedly I am not very good with them.</p>
  
  <p>Here is a MWE. How can I overcome this?</p>
  
  <pre><code>library(reshape2)
  
  data &lt;- c("Medtr0001s0360.1", "Medtr0001s0430.1", "Medtr0001s0490.1", 
  "Medtr0001s0570.1", "Medtr0001s0570.2", "Medtr0001s0570.3")
  
  GO_terms &lt;- colsplit(data, pattern=".", c("a", "b"))
  GO_terms
     a               b
  1 NA edtr0001s0360.1
  2 NA edtr0001s0430.1
  3 NA edtr0001s0490.1
  4 NA edtr0001s0570.1
  5 NA edtr0001s0570.2
  6 NA edtr0001s0570.3
  </code></pre>