title: Calculating the quotient between two files and writing it into another file
body: <p>Using Python, I have two large (equally long) files in which the numbers are divided by spaces:</p>
  
  <p>0.11158E-13 0.11195E-13 0.11233E-13 ... # file1</p>
  
  <p>0.11010E-13 0.11070E-13 0.11117E-13 ... # file2</p>
  
  <p>There are differences in the values and I would like to  get the relative differences and writing them in the same format into a third file.
  I can do it for the first value but have problem when it comes to ITERATING the process (so that all values are computed).</p>
  
  <p>This is the code (I am new to the python code):</p>
  
  <pre><code>with open('ex1.idl', 'r') as f1:      #this opens the first file
      with open('ex2.idl', 'r') as f2:      #this opens the second file
  
          f1 = f1.read(13)          # reading the length of the value (ex1.idl)
          f2 = f2.read(13)          # reading the length of the value (ex2.idl)
          f1 = float(f1)          #assigning the numerical value for the string
          f2 = float(f2)          #assigning the numerical value for the string
          c = f1/f2               #calculating relative values    
  
  with open('ex3.txt', 'w') as f3:          #opening the new file and
      f3.write(str(c))                      #writing into the new file as a string
  </code></pre>
  
  <p>Is this the way to go or should I go with a different approach? An answer is very much appreciated.</p>