title: How to remove duplicated column names in R?
body: <p>I have very big matrix,  I know that some of the colnames of them are duplicated. so I just want to find those duplicated colnames and remove on of the column from duplicate. 
  I tried <code>duplicate()</code>, but it removes the duplicate entries. 
  Would someone help me to implment this in R ?
  the point is that, duplicate colnames, might not have duplicate entires.</p>