Matplotlib - 仅使用 Y 坐标突出显示已绘制图形中的点

Question

I have some stock data and I plotted the data index = x-axis , price = y-axis and now after calculating I have found an array of price ie sub array of price. I want to highlight the points in the array on the graph

I have tried markvery() documentation but cant understand its working. Here is my code

from matplotlib
import pyplot as plt


x =[ 1,2,3,4,5,6,7] # array to be plotted
y=[100,111,112,111,112,113,114] # array to be plotted

subArray = [111,114] # array to be highlighted
plt.plot(x,y)
plt.show()

Any Help would be appreciated

Answer 1

Your subArray contains two points which occur more than once in your y . So first you can get the indices of your subArray elements from y and then plot them separately again to highlight them. As@ImportanceOfBeingErnest pointed out, there is no in-built general approach for this.

That being said, things become easier if you convert to NumPy array. Below is one way to find the indices among others listed here

import numpy as np

x =np.array([ 1,2,3,4,5,6,7]) # array to be plotted
y=np.array([100,111,112,111,112,113,114]) # array to be plotted

subArray = [111,114] 
ids = np.nonzero(np.in1d(y, subArray))[0]

plt.plot(x,y)
plt.plot(x[ids], y[ids], 'bo')