title: Convert a date to a day number (monday = 1, tuesday = 2) in R
body: <p>Can someone help me with the following:</p>
  
  <p>I have a date, for example: 3-1-2014,</p>
  
  <p>And I would like to convert this to the number 5, because it is a friday.</p>
  
  <p>So 7-1-2014 would be 1, because it is a monday.</p>
  
  <p>Which package/code can do this for me?</p>
  
  <p>Thanks</p>