python - 在matplotlib中绘制实时图递归错误

Question

我正在尝试使用下面的代码从 pandas 数据帧动态绘制图表。问题是 update_graph() 行给出错误 ( https://gist.github.com/ishikawa-rei/759d9063c3add40712cd5a16696f9532 )。如果我注释掉该行，代码就会运行，但图表上不会按预期显示任何内容。数据取自 csv 文件，该文件有一行数据，当某些内容发生变化时会更新，并且仅包含 -100 到 100 之间的值，如下例。

google ... amazon ... apple
77         50         -100

.

import matplotlib
matplotlib.use('TkAgg')

import numpy as np
import matplotlib.pyplot as plt
import pandas as pd

objects = ("google","ibm","kaspersky","amazon","facebook","sony","microsoft","apple")

def update_graph():
    fig.clear()
    cols = ["google","ibm","kaspersky","amazon","facebook","sony","microsoft","apple"]
    df = pd.read_csv("C:/Users/dmnte/PycharmProjects/sentiment_analysis/live_information.csv",header=None,  names=cols,encoding = "UTF-8",low_memory=False)
    y_pos = np.arange(len(objects))
    performance = df.values.tolist()
    flat_list = [item for sublist in performance for item in sublist]
    plt.bar(y_pos, flat_list, align='center', alpha=0.5)
    plt.xticks(y_pos, objects)
    plt.ylabel('company sentiment (%)')
    plt.title('Real time company sentiment')
    fig.canvas.draw()
    win.after(20000, update_graph())

fig = plt.figure()
win = fig.canvas.manager.window
update_graph()
plt.show()

Answer 1

我认为您的代码的唯一问题是您没有将 update_graph 函数的引用传递给 win.after() 而是执行后的返回值update_graph() 的。我想说的是:作为参数传递 update_graph 和 update_graph() 之间是有区别的。

这是一个工作玩具代码，我在其中更改了数据加载。您可以插入自己的 get_data() 函数，在其中加载 .csv 文件。

import matplotlib
matplotlib.use('TkAgg')

import numpy as np
import matplotlib.pyplot as plt
import pandas as pd


objects = ("google","ibm","kaspersky","amazon","facebook","sony","microsoft","apple")

def get_data():
    return np.random.randint(1,100, len(objects))

def update_graph():
    fig.clear()
    y_pos=np.arange(len(objects))
    data=get_data()
    plt.bar(y_pos, data, align="center", alpha=0.5)
    plt.xticks(y_pos, objects)
    plt.ylabel("company sentiment (%)")
    plt.title("Real time company sentiment")
    fig.canvas.draw()
    fig.canvas.manager.window.after(100, update_graph)


fig = plt.figure()
win = fig.canvas.manager.window
win.after(100, update_graph)
plt.show()