title: Extarcting top ten values from each column and for each year in R programming
body: <p>I have a three hourly time series from 1998-2018. There are many columns. First column is Time. rest of the each column represent temperature at a specific site. I want to extract top ten values for each year and for each site. I mean from each column I need top ten values for each year. Could any one please help me to solve it in R. </p>
  
  <p><a href="https://i.stack.imgur.com/Xdyuc.png" rel="nofollow noreferrer">data example</a></p>
  
  <p>I have shown daily data here.
  For each year, now i want to extract first top ten values.  (first ten maximum values) for each station  I have twenty years of data.
  so for a given station i will be having 20 *10 =200 values. But i want to do it for all stations. I used dplyr and group_by and top_n option. but there i could do it for only one column. But i need it for every column</p>