title: Interpolation for 3D surface
body: <p>I have my data in an ndarray of size 21 by 30; it contains velocity values at each point. I have made a 3D surface plot to visualize it but the data is not so smooth. In order to interpolate the data, so that I have smooth peaks, I tried the function <code>griddata</code> but it does not seem to work.</p>
  <p>Here is my code:</p>
  <pre><code>import numpy as np
  import matplotlib.pyplot as plt
  vel = np.genfromtxt(r'velocity.txt')
  x = np.arange(0, 21, 1)
  y = np.arange(0, 30, 1)
  fig = plt.figure()
  ax = fig.add_subplot(111, projection='3d')
  X,Y = np.meshgrid(x, y)
  surf = ax.plot_surface(x, y, vel, cmap=&quot;RdBu&quot;)
  fig.set_size_inches(10, 10)
  plt.show()
  </code></pre>