title: Matrix manipulation in numpy
body: <p>I wrote the code below:</p>
  
  <pre><code>import os
  import csv
  import numpy as np
  
  ROOT_PATH = os.path.dirname(os.path.abspath(__file__)) # These two lines give the 
  path = os.path.join(ROOT_PATH, "0.dat")  # path to a file on my disk
  
  with open(path, 'r') as f1:
      listme = csv.reader(f1, delimiter="\t") # I imported the file
      listme2 = list(listme) # I used this command to make a matrix in the next line
      m = np.matrix(listme2)
      m2 = np.delete(m,[1,2],1) # I deleted two columns to get a 2 by 2 matrix
  
  print m + m # It cannot add these two matrix. It also cannot multiply them by np.dot(m,m)
  </code></pre>
  
  <p>I cannot add the matrix I defined to itself. Please read the comment in the code.</p>
  
  <p>The error returned is:</p>
  
  <pre><code>TypeError: unsupported operand type(s) for +: 'matrix' and 'matrix' 
  </code></pre>