title: Get names of specific members of clusters of heatmap() function R
body: <p>Once you generate a heat map using 'heatmap()' function in R, is there a way to focus in and extract the members of a specific cluster? </p>
  
  <p>I have a heat map of 4500 x 420 members and it would be useful. </p>
  
  <p>Thanks. </p>