How To Draw A Triangle Using Matplotlib.pyplot Based On 3 Dots (x,y) In 2d?

I would like to draw a triangle using python3 module matplotlib. import numpy as np import matplotlib.pyplot as plt X_train = np.array([[1,1], [2,2.5], [3, 1], [8, 7.5], [7, 9],

Solution 1:

A triangle is a polygon. You may use plt.Polygon to draw a polygon.

import numpy as np 
import matplotlib.pyplot as plt

X = np.array([[1,1], [2,2.5], [3, 1], [8, 7.5], [7, 9], [9, 9]])
Y = ['red', 'red', 'red', 'blue', 'blue', 'blue']

plt.figure()
plt.scatter(X[:, 0], X[:, 1], s = 170, color = Y[:])

t1 = plt.Polygon(X[:3,:], color=Y[0])
plt.gca().add_patch(t1)

t2 = plt.Polygon(X[3:6,:], color=Y[3])
plt.gca().add_patch(t2)

plt.show()