title: Unable to install scikit-image
body: <p>I'm working on a Mac with python 2.7.
  Whenever i'm trying to install scikit-image
  Command used to install : <code>sudo pip install scikit-image</code>, i'm getting the below error :</p>
  
  <pre><code>Requirement already satisfied: python-dateutil in /System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python (from matplotlib&gt;=1.3.1-&gt;scikit-image) (1.5)
  Requirement already satisfied: tornado in /Library/Python/2.7/site-packages (from matplotlib&gt;=1.3.1-&gt;scikit-image) (5.0.2)
  Requirement already satisfied: pyparsing&gt;=1.5.6 in /System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python (from matplotlib&gt;=1.3.1-&gt;scikit-image) (2.0.1)
  Requirement already satisfied: nose in /Library/Python/2.7/site-packages (from matplotlib&gt;=1.3.1-&gt;scikit-image) (1.3.7)
  Requirement already satisfied: futures in /Library/Python/2.7/site-packages (from tornado-&gt;matplotlib&gt;=1.3.1-&gt;scikit-image) (3.2.0)
  Requirement already satisfied: singledispatch in /Library/Python/2.7/site-packages (from tornado-&gt;matplotlib&gt;=1.3.1-&gt;scikit-image) (3.4.0.3)
  Requirement already satisfied: backports_abc&gt;=0.4 in /Library/Python/2.7/site-packages (from tornado-&gt;matplotlib&gt;=1.3.1-&gt;scikit-image) (0.5)
  Installing collected packages: numpy, PyWavelets, scipy, six, decorator, networkx, scikit-image
    Found existing installation: numpy 1.8.0rc1
  Cannot uninstall 'numpy'. It is a distutils installed project and thus we cannot accurately determine which files belong to it which would lead to only a partial uninstall.
  </code></pre>