title: Vector-vector multiplication to create a matrix
body: <p>I am an IDL user slowly switching to numpy/scipy, and there is an operation that I do extremely often in IDL but cannot manage to reproduce with numpy:</p>
  <pre><code>IDL&gt; a = [2., 4]
  IDL&gt; b = [3., 5]
  IDL&gt; print,a # b
        6.00000      12.0000
        10.0000      20.0000
  </code></pre>
  <p>I'm not even sure of about the name of this operation. Maybe it is obvious how to do it in numpy, but I could not find a simple way.</p>