title: installing matplotlib package for Python 2.7 on windows 7 (64 bit)
body: <p>I already installed Python 2.7 on my PC (windows 7 with64 bit) using this web page(<a href="https://www.continuum.io/downloads" rel="nofollow">https://www.continuum.io/downloads</a>). Finally when I tried in my new cell the followin program, it didn't work. So I think I should install numpy and mathplotlib packages.  I actually  tried as <code>pip install numpy matplotlib</code>, and it says it is already satisfied. But, it has not worked yet. How could I install alternatively by using <code>pip</code>? Thanks.</p>
  
  <pre><code>import numpy as np
  import scipy
  from scipy import special
  import matplotlib.pyplot as plt
  %matplotlib inline
  x = np.linspace(0, 10, 100)
  fig, ax = plt.subplots()
  for n in range(4):
   ax.plot(x, scipy.special.jn(n, x),
  label=r"$J_%d(x)$" % n)
  ax.legend();
  </code></pre>