title: Reading a text file in MATLAB line by line
body: <p>I have a CSV file, I want to read this file and do some pre-calculations on each row to see for example that row is useful for me or not and if yes I save it to a new CSV file. 
  can someone give me an example?
  in more details this is how my data looks like: (string,float,float) the numbers are coordinates.</p>
  
  <pre><code>ABC,51.9358183333333,4.183255
  ABC,51.9353866666667,4.1841
  ABC,51.9351716666667,4.184565
  ABC,51.9343083333333,4.186425
  ABC,51.9343083333333,4.186425
  ABC,51.9340916666667,4.18688333333333
  </code></pre>
  
  <p>basically i want to save the rows that have for distances more than 50 or 50 in a new file.the string field should also be copied.
  thanks</p>