title: python - How to find the image of an array x1 with a curve made with array (x,y)?
body: <p>Thanks to whoever is reading this question.</p>
  <p>I have a plot (from two same-sized arrays: x and y).
  I have another array x1 and want to find the corresponding array y1 by the same plotted function.</p>
  <p>Mathematically, this would give:
  I have f(x)=y (x and y are two arrays)
  I want to find f(x1) (same f, different x).</p>
  <p>This is my code:</p>
  <pre><code>from matplotlib import pyplot as plt
  import numpy as np
  
  y_vek = []
  x = np.linspace (0,1,20)
  y = [0,3,4,5,7,6,34,3,42,53,5,57,67,67,5,67,65,21,6,0] 
  
  plt.plot (x,y,'g',label='y')
  plt.legend()
  plt.tight_layout()
  plt.grid(True)
  plt.show()
  </code></pre>
  <p>In my case, f is defined by the arrays x and y.
  Now I have an x1 different from x (same-sized with x) and want to find f(x1).</p>
  <p>Is there a way to find that?</p>