title: get row and column of matrix
body: <p>I wonder where how to get row and column of this matrix. I want to loop through each element[row][column], but I have no idea how to get these.</p>
  
  <pre><code>imaginary_axis = 100
  real_axis = 1
  
  mixed_matrix = [[0 for j in xrange(imaginary_axis)] for i in xrange(real_axis)]
  
  for row in mixed_matrix[0]:
      print(row)
      for column in mixed_matrix:
           print(column)
           check(mixed_matrix[row][column])
  </code></pre>
  
  <p>This throws an error. How can I get this to work?</p>
  
  <pre class="lang-none prettyprint-override"><code>TypeError: list indices must be integers, not list
  </code></pre>
  
  <p>I know why I get this error, but I do not know how I can get the column right.</p>