在添加更多之前等到用户删除 Matplotlib 图的方法？

Question

所以我有一个函数可以散点图绘制一些数据，并通过创建新图形来实现。一次允许的最大数字量为 20，以避免内存过载。如果用户想要精确地绘制具有 6 个变量的数据集，那么将有 30 个不同的图形。有没有办法等到用户删除了必要数量的数字再添加更多？

这是我想到的：

import matplolib.pyplot as plt
... # some code
# this below is inside a loop structure
f = plt.figure
# add some stuff to the figure
plt.show(block=False)
Halt()  # checks to see if there are too many figures

其中 Halt() 定义如下：

def halt():
    first = True
    while plt.gcf().number > 20:  # are there more than 20 figures
        if first:
            # show message
            first  = False
            # time.sleep(100)

唯一的问题是它“冻结”了程序，不允许用户退出任何数字，因为它“没有响应”。我也试过 time.sleep() 但这似乎也不起作用。

有人知道循环直到满足条件的好方法吗？

Answer 1

https://matplotlib.org/api/_as_gen/matplotlib.pyplot.show.html 说：

If False ensure that all windows are displayed and return immediately. In this case, you are responsible for ensuring that the event loop is running to have responsive figures.

如何做到这一点，你问？好吧，文档位于 https://matplotlib.org/users/interactive_guide.html#explicitly-spinning-the-event-loop .

经过一些摆弄，我做了以下同时绘制 20 个数字，最多 5 个：

import matplotlib.pyplot as plt
import numpy as np
from time import sleep

def plot_stuff(exponent, titlenum):
    x = np.linspace(0.0, 1.0)
    f = plt.figure()
    ax = f.add_subplot(1, 1, 1)
    ax.set_title('{} - {}'.format(titlenum, exponent))
    ax.plot(x, x**exponent)

def get_fighandles():
    fignumbers = plt.get_fignums()
    return [plt.figure(fign) for fign in fignumbers]

N_figs_eventually_plotted = 20
N_figs_max_simultaneous = 5

N=0
while N < N_figs_eventually_plotted:
    if len(get_fighandles()) < N_figs_max_simultaneous:
        N += 1
        # put here whichever update is needed when you can add new figures
        plot_stuff(np.random.random(), N)
        plt.show(block=False)
    print('hi')
    for fig in get_fighandles():
        print(fig.canvas)
        fig.canvas.flush_events()
        fig.canvas.draw_idle() # might not be needed, but here it's fast
    sleep(0.1)

# note: solution terminates when the last figure is plotted, you might want something to prevent this (for instance a plt.show(block=True) when the last figure is plotted)

可能存在一些微妙的并发错误（例如，如果您在循环读取图窗句柄之后但在刷新事件之前关闭图窗），但我看不出如何在您的用例中避免这种情况.

在添加更多之前等到用户删除 Matplotlib 图的方法？

Way to wait until user deletes Matplotlib figure before adding more?

python

sleep

matplotlib

pause