Matplotlib animate plot - Figure not responding until loop is done

Question

I am trying to animate a plot where my two vectors X,Y are updating through a loop. I am using FuncAnimation. The problem I am running into is the Figure would show Not Responding or Blank until the loop is completed.

So during the loop, I would get something like:

But if I stopped the loop or at the end, the figure would appear.

I have set my graphics backend to automatic.

Here is the example of the code:

import matplotlib.pyplot as plt
from matplotlib.animation import FuncAnimation

def animate( intermediate_values):
    x = [i for i in range(len(intermediate_values))]
    y = intermediate_values 
    plt.cla()
    plt.plot(x,y, label = '...')
    plt.legend(loc = 'upper left')
    plt.tight_layout()        
    
    
x = []
y = []
#plt.ion()
for i in range(50):
    x.append(i)
    y.append(i)
    ani = FuncAnimation(plt.gcf(), animate(y), interval = 50)  
    plt.tight_layout()
    #plt.ioff()
    plt.show()

user_13107804 · Answer

The structure of animation in matplotlib is that the animation function is not used in the loop process, but the animation function is the loop process. After setting up the initial graph, the animation function will update the data.

import matplotlib.pyplot as plt
from matplotlib.animation import FuncAnimation

x = []
y = []

fig = plt.figure()
ax = plt.axes(xlim=(0,50), ylim=(0, 50))
line, = ax.plot([], [], 'b-', lw=3, label='...')
ax.legend(loc='upper left')


def animate(i):
    x.append(i)
    y.append(i)
    line.set_data(x, y)
    return line,

ani = FuncAnimation(fig, animate, frames=50, interval=50, repeat=False)

plt.show()

Matplotlib animate plot - Figure not responding until loop is done

1 Answers