title: Multiplication operator for scipy sparse matrices
body: <p>I'm a little bit confused by the behavior of the multiplication operator <code>*</code> when scipy sparse matrices are involved. It seems the operator implements matrix multiplication, not component-wise multiplication as it would with numpy arrays.</p>
  
  <p>Some code to check this:</p>
  
  <pre><code>from scipy.sparse import lil_matrix
  A = lil_matrix(-numpy.eye(2))
  b = lil_matrix(numpy.ones((2,2)))
  print (A * B).toarray()
  </code></pre>
  
  <p>results in:</p>
  
  <pre><code>[[-1. -1.]
   [-1. -1.]]
  </code></pre>
  
  <p>The <a href="http://docs.scipy.org/doc/scipy/reference/sparse.html#module-scipy.sparse" rel="nofollow">documentation</a> of the <code>scipy.sparse</code> module does not really go into details on this, and I wonder whether there is a clear specification of the multiplication behavior somewhere?</p>
  
  <p>Furthermore, are there some clearly defined rules for multiplication operator with scipy sparse matrices and numpy matrices or arrays?</p>