title: How to change values of a numpy array
body: <p>I have a numpy array 'X' of shape(826,2). I have another numpy array of zeros 'X_expanded' of shape(X.shape[0], 6). I want to replace the elements of the X_expanded with feature0, feature1, feature0^2, feature1^2, feature1*feature2, 1 of the array X.</p>
  
  <p>For example</p>
  
  <pre><code>X = np.array([
      [0,0],
      [1,0],
      [2.61,-1.28],
      [-0.59,2.1]
  ])
  </code></pre>
  
  <p>I want X_expanded to be</p>
  
  <pre><code>([[ 0.    ,  0.    ,  0.    ,  0.    ,  0.    ,  1.],
    [ 1.    ,  0.    ,  1.    ,  0.    ,  0.    ,  1.],
    [ 2.61  , -1.28  ,  6.8121,  1.6384, -3.3408,  1.],
    [-0.59  ,  2.1   ,  0.3481,  4.41  , -1.239 ,  1.]])
  </code></pre>