使用Matplotlib Animation出现MatplotlibDeprecationWarning的解决求助

我在开发Arduino实时数据绘图脚本时，运行代码后出现了以下Matplotlib弃用警告：

MatplotlibDeprecationWarning: Support for FigureCanvases without a required_interactive_framework attribute was deprecated in Matplotlib 3.6 and will be removed two minor releases later.

使用的脚本代码如下：

import time
import serial
import comport as com
import matplotlib.pyplot as plt
import matplotlib.animation as animation


def animate(i, dataList, ser):
    arduinoData_string = ser.readline().decode('ascii')  # Decode receive Arduino data as a formatted string
    # print(i)                                           # 'i' is a incrementing variable based upon frames = x argument

    try:
        arduinoData_float = float(arduinoData_string)  # Convert to float
        dataList.append(arduinoData_float)  # Add to the list holding the fixed number of points to animate

    except:  # Pass if data point is bad
        pass

    dataList = dataList[-50:]  # Fix the list size so that the animation plot 'window' is x number of points

    ax.clear()  # Clear last data frame
    ax.plot(dataList)  # Plot new data frame

    ax.set_ylim([0, 1200])  # Set Y axis limit of plot
    ax.set_title("Arduino Data")  # Set title of figure
    ax.set_ylabel("Value")  # Set title of y axis


dataList = []  # Create empty list variable for later use

fig = plt.gcf()  # Create Matplotlib plots fig is the 'higher level' plot window
ax = fig.add_subplot(111)  # Add subplot to main fig window

ser = com.ini('COM2')
time.sleep(2)  # Time delay for Arduino Serial initialization

# Matplotlib Animation Fuction that takes takes care of real time plot.
# Note that 'fargs' parameter is where we pass in our dataList and Serial object.
# ani = FuncAnimation(fig, animate, frames=100, fargs=(dataList, ser), interval=100)

ani = animation.FuncAnimation(fig, animate, frames=100, fargs=(dataList, ser), interval=100)

plt.show()  # Keep Matplotlib plot persistent on screen until it is closed
ser.close()

环境配置：PyCharm最新版本，Matplotlib 3.7.1

解决方法 #

这个警告的核心原因是Matplotlib 3.6及以上版本要求交互式画布必须明确指定框架，以下是几种可行的解决方式：

• 显式指定Matplotlib交互式后端
  在脚本最开头添加代码，指定一个兼容的交互式后端（比如Qt5Agg、TkAgg），注意要放在导入matplotlib.pyplot之前：

  import matplotlib
  matplotlib.use('Qt5Agg')
  

• 替换plt.gcf()为显式创建Figure对象
  原代码中fig = plt.gcf()可能导致画布初始化不规范，改为直接创建Figure和Axes对象，既简化代码又能确保画布正确初始化：

  fig, ax = plt.subplots()
  

• 修改PyCharm的绘图显示设置
  打开PyCharm的Settings → Tools → Python Scientific，取消勾选Show plots in tool window。这样Matplotlib会使用系统默认的交互式窗口显示绘图，避免内嵌工具窗口带来的后端兼容问题。

修改后的完整脚本示例 #

结合前两种解决方法，修改后的代码如下：

import matplotlib
matplotlib.use('Qt5Agg')  # 先指定交互式后端
import time
import serial
import comport as com
import matplotlib.pyplot as plt
import matplotlib.animation as animation


def animate(i, dataList, ser):
    arduinoData_string = ser.readline().decode('ascii')

    try:
        arduinoData_float = float(arduinoData_string)
        dataList.append(arduinoData_float)
    except:
        pass

    dataList = dataList[-50:]

    ax.clear()
    ax.plot(dataList)

    ax.set_ylim([0, 1200])
    ax.set_title("Arduino Data")
    ax.set_ylabel("Value")


dataList = []
fig, ax = plt.subplots()  # 显式创建Figure和Axes

ser = com.ini('COM2')
time.sleep(2)

ani = animation.FuncAnimation(fig, animate, frames=100, fargs=(dataList, ser), interval=100)

plt.show()
ser.close()

内容的提问来源于stack exchange，提问作者Valery Utukin