title: How do I delete the first column in my matrix in python?
body: <p>I have a matrix and want to delete the first column in python.  What is the best way to do that?</p>
  
  <p>Ex:  Get rid of the first column of E.  </p>
  
  <pre><code>    E E E E E
      E 1 2 3 4
      E 5 6 7 8
      E 9 1 2 3
  </code></pre>
  
  <p>The matrix is being read in from a txt file.  I am trying to use the first row as keys, get rid of the first column and use the remaining rows as values.</p>
  
  <p>Here is what I have so far:  </p>
  
  <pre><code>    matrix_filename = raw_input("Enter the scoring matrix filename:  ")  
      matrix_file = open(matrix_filename, "r")  
      matrix = matrix_file.readlines()  
      keys = matrix[0]  
      vals = matrix[1:]  
  </code></pre>
  
  <p>I want the values to be the numbers only.  </p>
  
  <p>Thanks, guys!</p>