matplotlib not responding after a interactive plotting

Question

I was working on a project using Arduino with python, I was plotting real-time sensor data from Arduino using libraries(pyfirmata,matplot,draw now) I am getting the real-time output but after the fixed iteration the figure got not responding. I attached the code below

import pyfirmata
import time
import matplotlib.pyplot as plt
from drawnow import *
import sys
board = pyfirmata.Arduino('COM8')
iter8 = pyfirmata.util.Iterator(board)
iter8.start()

LED = board.get_pin('d:13:o')
ldr=board.get_pin('a:0:o')
val=0
converted=1023
converted2=5.0/1023.0
s=[]
i=0

def makeFig():

    plt.figure(1)
    plt.ion()
    plt.plot(s)
    plt.title('My Live Streaming Sensor Data')  # Plot the title
    plt.grid(True)

while(i<=50):

    time.sleep(0.01)
    val=ldr.read()
    print(val * converted * converted2)
    s.append(val)
    i=i+1
    drawnow(makeFig)  # Call drawnow to update our live graph
    plt.pause(.000001)
plt.show()

I want to save the sensor plotting after some iteration that is my ultimate goal

Answer 1

You probably want to call plt.ioff() before plt.show() .

More generally, better work completely inside the event loop as shown below.

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


board = pyfirmata.Arduino('COM8')
iter8 = pyfirmata.util.Iterator(board)
iter8.start()

LED = board.get_pin('d:13:o')
ldr=board.get_pin('a:0:o')
val=0
converted=1023
converted2=5.0/1023.0
s=[]
i=0

fig, ax = plt.subplots()
line,= ax.plot([],[])

def update(i):

    val=ldr.read()
    print(val * converted * converted2)
    s.append(val)
    line.set_data(range(len(s)), s)
    ax.autoscale()
    ax.relim()
    ax.autoscale_view()

FuncAnimation(fig, update, frames=50, repeat=False)

plt.show()