title: Plotting functions with SageMath, not Showing
body: <p>I have a problem where functions that I plot within SageMath aren't visually showing up. Even if I copy and paste code from the SageMath info pages, certain functions will not show up plotted for me. I'm using SageMath 8.1 Notebook. Here's example code:</p>
  
  <pre><code>import numpy as np
  import matplotlib.pyplot as plt    
  myPlot = plt.plot(np.array([0, 1, 2, 5]))
  show(myPlot)
  </code></pre>
  
  <p>Output:</p>
  
  <p><code>[Line2D(-line49)]</code></p>
  
  <p>Instead of a graph. As far as I can tell, this should output a visual graph rather than just the info in brackets. </p>
  
  <p>Some code I copy from the <a href="http://doc.sagemath.org/html/en/constructions/plotting.html#plotting-functions-in-2d" rel="nofollow noreferrer">SageMath Help Pages</a> works, such as: </p>
  
  <pre><code>v = [(1/cos(-pi/2+pi*i/100), tan(-pi/2+pi*i/100)) for i in range(1,200) if i!=100 ]
  L = [(a/(a^2+b^2), b/(a^2+b^2)) for a,b in v]
  </code></pre>
  
  <p>Which outputs a visual graph.</p>
  
  <p>I'm not sure what I'm doing wrong here. </p>