title: Inverse function of numpy.polyval()
body: <p>I was wondering is there a convenient inverse function of np.polyval(), where I give the y value and it solves for x?</p>
  
  <p>I know one way I could do this is:</p>
  
  <pre><code>import numpy as np
  
  # Set up the question
  p = np.array([1, 1, -10])
  y = 100
  
  # Solve
  p_temp = p
  p_temp[-1] -= y
  x = np.roots(p_temp)
  </code></pre>
  
  <p>However my guess is most would agree on that this code has low readability. Any suggestions?</p>