title: Get week starting date from weeknum and year in R
body: <p>I'm looking for a function that will get year + week number + Week day, and return a date, for example:</p>
  
  <p>I would like to input the 3 following </p>
  
  <pre><code> 2015
   Monday
   23
  </code></pre>
  
  <p>And get the desired output:</p>
  
  <pre><code>"2015-06-08"
  </code></pre>
  
  <p>After Searching in the Web, there seems to be  equivalent question in other languages but not in R:</p>
  
  <p><a href="https://stackoverflow.com/questions/17449810/how-to-get-date-from-week-number-and-year">How to Get date from week number and year</a></p>
  
  <p>Any help on that would be great!</p>