如何在OpenCV中绘制xy坐标

Question

在本教程中，如何在不使用随机数的情况下绘制数据x和y坐标？否则，我该如何更改形状的颜色？

import cv2
import numpy as np
import matplotlib.pyplot as plt

trainData = np.random.randint(0,100,(25,2)).astype(np.float32)

responses = np.random.randint(0,2,(25,1)).astype(np.float32)

red = trainData[responses.ravel()==0]
plt.scatter(red[:,0],red[:,1],80,'r','^')

blue = trainData[responses.ravel()==1]
plt.scatter(blue[:,0],blue[:,1],80,'b','s')

newcomer = np.random.randint(0,100,(1,2)).astype(np.float32)
plt.scatter(newcomer[:,0],newcomer[:,1],80,'g','o')

knn = cv2.KNearest()
knn.train(trainData,responses)
ret, results, neighbours ,dist = knn.find_nearest(newcomer, 3)

print "result: ", results,"\n"
print "neighbours: ", neighbours,"\n"
print "distance: ", dist

plt.show()