title: Find files based on a date in the filename
body: <p>I have 100 text files in a directory.</p>
  
  <p>The format of the filename is  <code>abcd_2011_04_20.txt</code></p>
  
  <p>I need to read only TODAY's file and the past 7 days files . How do I go about it?
  EDIT 1 :</p>
  
  <p>I already have a function dirTxt(dirname) which returns the name of the files as an array . How do I identify the current date's corresponding file?? and then get the previous 7 day's files??  </p>
  
  <p>EDIT 2 :</p>
  
  <p>THE array returns the following</p>
  
  <p>'graph.txt' 
    'graph1.txt' 
  'abcd_2011-04-12.txt' 
    'abcd_2011-04-13.txt' 
    'abcd_2011-04-24.txt' 
    'abcd_2011-04-15.txt' 
    'abcd_2011-04-16.txt' 
    'abcd_2011-04-17.txt' 
    'abcd_2011-04-18.txt' 
    'abcd_2011-04-19.txt' 
    'abcd_2011-04-20.txt' </p>