title: Trying to understand NumPy's linalg.norm method
body: <p>I do not understand what this code is doing. X is a matrix which each row of it is an eigenvector of an image. What does the norm do?</p>
  
  <pre><code>   # Take an eigenvector and make it into an image
      def vecToImage(x, size = lfw_imageSize):
        im = x/np.linalg.norm(x)
        im = im*(256./np.max(im))
        im.resize(*size)
        return im
  </code></pre>