title: how to plot coordinate points to an image
body: <p>I have retrieved coordinate points of an image from this code to an array.how can I plot this coordinate points in to an image.</p>
  
  <pre><code>import numpy as np
  import matplotlib.pyplot as plt
  import cv2
  
  img = cv2.imread('2.jpg')
  edge = cv2.Canny(img, 100, 200)
  
  ans = []
  for y in range(0, edge.shape[0]):
      for x in range(0, edge.shape[1]):
          if edge[y, x] != 0:
              ans = ans + [[x, y]]
  ans = np.array(ans)
  
  print(ans.shape)
  print(ans[0:10, :])
  </code></pre>