Closed
Description
Bug summary
If a fig with an ax using the indicate_inset_zoom is saved to pdf and then pickled, one gets the following error:
TypeError: cannot pickle '_io.BufferedWriter' object
Code for reproduction
import pickle
import matplotlib.pyplot as plt
def plot(inset_zoom: bool, format: str):
fig, ax = plt.subplots()
ax.plot(
[1, 1],
[2, 2],
)
if inset_zoom:
ax.indicate_inset_zoom(ax)
if format is not None:
fig.savefig(f"./test1.{format}", format=f"{format}")
pickle.dumps(fig)
for format in (None, "png", "pdf"):
for inset_zoom in (False, True):
print(f"format: {format} inset_zoom {inset_zoom}")
plot(inset_zoom, format)
print("ok")Actual outcome
(venv) C:\Users\Moi4\Desktop\code\test\pickle_buffwr_err>python error_with_mpl_pickle.py
format: None inset_zoom False
ok
format: None inset_zoom True
ok
format: png inset_zoom False
ok
format: png inset_zoom True
ok
format: pdf inset_zoom False
ok
format: pdf inset_zoom True
Traceback (most recent call last):
File "C:\Users\Moi4\Desktop\code\test\pickle_buffwr_err\error_with_mpl_pickle.py", line 24, in <module>
plot(inset_zoom, format)
File "C:\Users\Moi4\Desktop\code\test\pickle_buffwr_err\error_with_mpl_pickle.py", line 18, in plot
pickle.dumps(fig)
TypeError: cannot pickle '_io.BufferedWriter' object
Expected outcome
The expected outcome would be no TypeError
Additional information
Saving to pickle before saving the figure is a workaround.
Operating system
Windows 10
Matplotlib Version
3.7.1 and 3.8.3
Matplotlib Backend
TkAgg
Python version
3.10.11
Jupyter version
No response
Installation
pip