Bug summary
When a figure is unpickled, it's dpi is doubled. This behaviour happens every time and if done in a loop it can cause an OverflowError.
Code for reproduction
import numpy as np
import matplotlib
import matplotlib.pyplot as plt
import pickle
import platform
print(matplotlib.get_backend())
print('Matplotlib ver:', matplotlib.__version__)
print('Platform:', platform.platform())
print('System:', platform.system())
print('Release:', platform.release())
print('Python ver:', platform.python_version())
def dump_load_get_dpi(fig):
with open('sinus.pickle','wb') as file:
pickle.dump(fig, file)
with open('sinus.pickle', 'rb') as blob:
fig2 = pickle.load(blob)
return fig2, fig2.dpi
def run():
fig = plt.figure()
x = np.linspace(0,2*np.pi)
y = np.sin(x)
for i in range(32):
print(f'{i}: {fig.dpi}')
fig, dpi = dump_load_get_dpi(fig)
if __name__ == '__main__':
run()Actual outcome
MacOSX
Matplotlib ver: 3.5.2
Platform: macOS-12.4-arm64-arm-64bit
System: Darwin
Release: 21.5.0
Python ver: 3.9.12
0: 200.0
1: 400.0
2: 800.0
3: 1600.0
4: 3200.0
5: 6400.0
6: 12800.0
7: 25600.0
8: 51200.0
9: 102400.0
10: 204800.0
11: 409600.0
12: 819200.0
13: 1638400.0
14: 3276800.0
15: 6553600.0
16: 13107200.0
17: 26214400.0
18: 52428800.0
19: 104857600.0
20: 209715200.0
21: 419430400.0
Traceback (most recent call last):
File "/Users/wsykala/projects/matplotlib/example.py", line 34, in <module>
run()
File "/Users/wsykala/projects/matplotlib/example.py", line 30, in run
fig, dpi = dump_load_get_dpi(fig)
File "/Users/wsykala/projects/matplotlib/example.py", line 20, in dump_load_get_dpi
fig2 = pickle.load(blob)
File "/Users/wsykala/miniconda3/envs/playground/lib/python3.9/site-packages/matplotlib/figure.py", line 2911, in __setstate__
mgr = plt._backend_mod.new_figure_manager_given_figure(num, self)
File "/Users/wsykala/miniconda3/envs/playground/lib/python3.9/site-packages/matplotlib/backend_bases.py", line 3499, in new_figure_manager_given_figure
canvas = cls.FigureCanvas(figure)
File "/Users/wsykala/miniconda3/envs/playground/lib/python3.9/site-packages/matplotlib/backends/backend_macosx.py", line 32, in __init__
_macosx.FigureCanvas.__init__(self, width, height)
OverflowError: signed integer is greater than maximum
Expected outcome
MacOSX
Matplotlib ver: 3.5.2
Platform: macOS-12.4-arm64-arm-64bit
System: Darwin
Release: 21.5.0
Python ver: 3.9.12
0: 200.0
1: 200.0
2: 200.0
3: 200.0
4: 200.0
5: 200.0
6: 200.0
7: 200.0
8: 200.0
9: 200.0
10: 200.0
11: 200.0
12: 200.0
13: 200.0
14: 200.0
15: 200.0
16: 200.0
17: 200.0
18: 200.0
19: 200.0
20: 200.0
21: 200.0
22: 200.0
Additional information
This seems to happen only on M1 MacBooks and the version of python doesn't matter.
Operating system
OS/X
Matplotlib Version
3.5.2
Matplotlib Backend
MacOSX
Python version
3.9.12
Jupyter version
No response
Installation
pip
Bug summary
When a figure is unpickled, it's dpi is doubled. This behaviour happens every time and if done in a loop it can cause an
OverflowError.Code for reproduction
Actual outcome
Expected outcome
Additional information
This seems to happen only on M1 MacBooks and the version of python doesn't matter.
Operating system
OS/X
Matplotlib Version
3.5.2
Matplotlib Backend
MacOSX
Python version
3.9.12
Jupyter version
No response
Installation
pip