title: How can the Euclidean distance be calculated with NumPy?
body: <p>I have two points in 3D space:</p>
  <pre><code>a = (ax, ay, az)
  b = (bx, by, bz)
  </code></pre>
  <p>I want to calculate the distance between them:</p>
  <pre><code>dist = sqrt((ax-bx)^2 + (ay-by)^2 + (az-bz)^2)
  </code></pre>
  <p>How do I do this with NumPy? I have:</p>
  <pre><code>import numpy
  a = numpy.array((ax, ay, az))
  b = numpy.array((bx, by, bz))
  </code></pre>