Question

我正在尝试创建一个动画情节，该情节将使用来自串行端口的数据进行实时更新。数据由Arduino以8x8阵列流式传输。数据是来自红外摄像机的温度。我能够创建图形的实例，但无法获取文本以使用串行流数据进行更新。

我试图设置'plt.show（block = False）'，以便脚本继续执行，但这使图形完全空了，并将其缩放到带有继续加载的加载光标的小窗口中。

我只希望文本使用数组数据以及新规范化数据中的颜色进行更新。

如何获取文本以使用matplotlib中的串行数据更新？

谢谢！

import numpy as np
import matplotlib
import matplotlib.pyplot as plt
import serial
import time

tempdata = serial.Serial("COM3",9600)
tempdata.timeout = 100
strn = []

rows = ["A", "B", "C", "D",
              "E", "F", "G","H"]
columns = ["1", "2", "3", "4",
              "5", "6", "7","8"]

print("AMG8833 8x8 Infrared Camera")
time.sleep(0.75)
print("Connected to: " + tempdata.portstr)
time.sleep(0.75)
print("Initializing Camera...")

tempsArray = np.empty((8,8))

while True: #Makes a continuous loop to read values from Arduino

    fig, ax = plt.subplots() 
    im = ax.imshow(tempsArray,cmap='plasma')
    tempdata.flush()
    strn = tempdata.read_until(']') #reads the value from the serial port as a string
    tempsString = np.asarray(strn)
    tempsFloat = np.fromstring(tempsString, dtype=float, sep= ', ')

     # Axes ticks
    ax.set_xticks(np.arange(len(columns)))
    ax.set_yticks(np.arange(len(rows)))
    # Axes labels
    ax.set_xticklabels(columns)
    ax.set_yticklabels(rows)
    # Rotate the tick labels and set their alignment.
    plt.setp(ax.get_xticklabels(), rotation=45, ha="right",
                     rotation_mode="anchor")

    tempsArray.flat=tempsFloat  
    im.set_array(tempsArray)

    ax.set_title("")
    fig.tight_layout()
    #Loop over data dimensions and create text annotations.
    for i in range(len(rows)):
        for j in range(len(columns)):
            text = ax.text(j, i, tempsArray[i, j],
                                ha="center", va="center", color="w")

    plt.show()

Heat Map

Answer 1

可以使用matplotlib的interactive mode实现此动态更新。您问题的答案与this one非常相似：基本上，您需要使用ion()启用交互模式，然后不调用show()更新图（或相关）功能。此外，在输入循环之前，只能创建一次图和子图。

这是修改后的示例：

import numpy as np
import matplotlib
import matplotlib.pyplot as plt
import serial
import time

tempdata = serial.Serial("COM3",9600)
tempdata.timeout = 100
strn = []

rows = ["A", "B", "C", "D",
              "E", "F", "G","H"]
columns = ["1", "2", "3", "4",
              "5", "6", "7","8"]

print("AMG8833 8x8 Infrared Camera")
time.sleep(0.75)
print("Connected to: " + tempdata.portstr)
time.sleep(0.75)
print("Initializing Camera...")

tempsArray = np.empty((8,8))

plt.ion()

fig, ax = plt.subplots()
# The subplot colors do not change after the first time
# if initialized with an empty matrix
im = ax.imshow(np.random.rand(8,8),cmap='plasma')

# Axes ticks
ax.set_xticks(np.arange(len(columns)))
ax.set_yticks(np.arange(len(rows)))
# Axes labels
ax.set_xticklabels(columns)
ax.set_yticklabels(rows)
# Rotate the tick labels and set their alignment.
plt.setp(ax.get_xticklabels(), rotation=45, ha="right",
                 rotation_mode="anchor")

ax.set_title("")
fig.tight_layout()

text = []

while True: #Makes a continuous loop to read values from Arduino

    tempdata.flush()
    strn = tempdata.read_until(']') #reads the value from the serial port as a string
    tempsString = np.asarray(strn)
    tempsFloat = np.fromstring(tempsString, dtype=float, sep= ', ')

    tempsArray.flat=tempsFloat  
    im.set_array(tempsArray)

    #Delete previous annotations
    for ann in text:
        ann.remove()
    text = []

    #Loop over data dimensions and create text annotations.
    for i in range(len(rows)):
        for j in range(len(columns)):
            text.append(ax.text(j, i, tempsArray[i, j],
                                ha="center", va="center", color="w"))

    # allow some delay to render the image
    plt.pause(0.1)

plt.ioff()

注意：这段代码对我有用，但是由于我现在没有Arduino，所以我用随机生成的帧序列（np.random.rand(8,8,10)）对其进行了测试，因此我可能忽略了一些细节。让我知道它是如何工作的。

如何使用Arduino的串行数据更新matplotlib中的文本？

1 个答案: