Is there a way to update the matplotlib plot without closing the window?

Question

I'm completely new to matplotlib and decently experienced but rusty with python and I'm struggling to work with matplotlib currently. I'm trying to kind of animate a point on the plot, kind of like this: https://www.desmos.com/calculator/rv8gbimhon

I've written the code for it but the plot doesn't update the point in real time during the while loop, instead, the while loop is paused until I close the plot window and the next iteration of the loop happens, re-opening the plot with the updated coords. Is there a way to move a point on matplotlib without opening and closing windows?

My code:

import numpy as np
import time
t = 0
start_time = time.time()
while t < 30:
    end_time = time.time()
    t = end_time - start_time
    print(t)
    plt.plot(t,t,"g^")
    plt.show()

Answer 1

One option to update the plot in a loop is to turn on interactive mode and to update the plot using pause.

For example:

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

point = plt.plot(0, 0, "g^")[0]
plt.ylim(0, 5)
plt.xlim(0, 5)
plt.ion()
plt.show()

start_time = time.time()
t = 0
while t < 4:
    end_time = time.time()
    t = end_time - start_time
    print(t)
    point.set_data(t, t)
    plt.pause(1e-10)

However, for more advanced animation I would propose to use the animation class.