如何在matplotlib动画中更新串口的值?

时间:2013-12-13 17:47:25

标签: python animation matplotlib arduino real-time

我一直在尝试使用matplotlib的动画功能实时绘制arduino的串行数据。数据来自ntc温度传感器。我能够获得的图表始终显示一条单线,并且该线条仅在温度变化时向上或向下平移。我想知道如何查看表示图中变化的曲线。这是代码:

import serial
from matplotlib import pyplot as plt
from matplotlib import animation
import numpy as np

arduino = serial.Serial('COM3', 9600)

fig = plt.figure()
ax = plt.axes(xlim=(0, 10), ylim=(10, 40))
line, = ax.plot([], [], lw=2)

def init():
    line.set_data([], [])
    return line,

def animate(i):
    x = np.linspace(0, 10, 1000)
    y = arduino.readline()
    line.set_data(x, y)
    return line,

anim = animation.FuncAnimation(fig, animate, init_func=init, frames=200, interval=20,        blit=False)

plt.show()

1 个答案:

答案 0 :(得分:2)

您正在将y数据设置为单个点(0,y)。你想做类似的事情:

max_points = 50
# fill initial artist with nans (so nothing draws)
line, = ax.plot(np.arange(max_points), 
                np.ones(max_points, dtype=np.float)*np.nan, 
                lw=2)
def init():
    return line,

def animate(i):
    y = arduino.readline()  # I assume this 
    old_y = line.get_ydata()  # grab current data
    new_y = np.r_[old_y[1:], y]  # stick new data on end of old data
    line.set_ydata(new_y)        # set the new ydata
    return line,