title: Create random numpy matrix of same size as another.
body: <p>This question <a href="https://stackoverflow.com/questions/35967907/how-to-make-a-new-numpy-array-same-size-as-a-given-array-and-fill-it-with-a-scal">here</a> was useful, but mine is slightly different. </p>
  
  <p>I am trying to do something simple here, I have a numpy matrix <strong>A</strong>, and I simply want to create another numpy matrix <strong>B</strong>, of the same shape as <strong>A</strong>, but I want <strong>B</strong> to be created from <code>numpy.random.randn()</code> How can this be done? Thanks. </p>