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plotting data from serial port with matplotlib
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
import serial
fig, ax = plt.subplots()
line, = ax.plot(np.random.rand(10))
ax.set_ylim(-5000, 5000)
xdata, ydata = [0]*100, [0]*100
raw = serial.Serial("/dev/ttyUSB1",9600)
raw.open()
def update(data):
line.set_ydata(data)
return line,
def run(data):
t,y = data
del xdata[0]
del ydata[0]
xdata.append(t)
ydata.append(y)
line.set_data(xdata, ydata)
return line,
def data_gen():
t = 0
while True:
t+=0.1
try:
dat = int(raw.readline())
except:
dat = 0
yield t, dat
ani = animation.FuncAnimation(fig, run, data_gen, interval=0, blit=True)
plt.show()
@Azzeccagarbugli
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Azzeccagarbugli commented Feb 20, 2017

Amazing man!
There is only a problem, when I start the script the plot is showed correctely, in a first moment, but after any seconds it is eraised by itself. How can I resolve this issue? Thanks a lot!

@Rainald62
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Rainald62 commented Sep 28, 2018

It seems that updating data by one line and updating the plot by one frame is linked. That way, it won't work for data rate > max frame rate, which is rather slow compared to other solutions using plt.ion(). It might be an inherent problem with animation.FuncAnimation(), as I havn't seen a working solution yet.
P.S.: A working solution with animation.FuncAnimation() and threads on reddit.

@xevilstar
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xevilstar commented Sep 6, 2020

what if I need a y scale that goes from 0 0.1 0.2 0.3 to 13 ?

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