Python matplotlib：显示后图形无法更新

Question

The following code works fine:

Python 3.8.2 (default, Apr  8 2020, 14:31:25) 
[GCC 9.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import matplotlib.pyplot as plt
>>> fig = plt.figure()
>>> fig.suptitle("Empty figure")
Text(0.5, 0.98, 'Empty figure')
>>> fig.show()

But if I set subtitle (or do any other thing) after show , it will not work, even I run show() again.

Python 3.8.2 (default, Apr  8 2020, 14:31:25) 
[GCC 9.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import matplotlib.pyplot as plt
>>> fig = plt.figure()
>>> fig.show()
>>> fig.suptitle("Empty figure")
Text(0.5, 0.98, 'Empty figure')
>>> fig.show()

I am new to python. Could anyone please help me?

Answer 1

In matplotlib, the .show() method by nature is designed to block any further execution of code after it is called until the shown figure is closed. Unless you turn on an interactive mode by calling .ion() before calling .show() , or there is an optional boolean parameter to be passed in to turn the blocking feature off as well:

plt.show(block=False)

Check out the documentation here: https://matplotlib.org/3.2.1/api/_as_gen/matplotlib.pyplot.show.html