Axis edge width not working

[vineetsoni]

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When I try to change the width of the axis, it does not work in the matplotlib2tikz export. However, the same works if one exports in PDF format.

Please have a look at the script below that would help you reproduce the issue:

import matplotlib.pyplot as plt
import numpy as np

N = np.zeros((512,512))

plt.rcParams['axes.edgecolor'] = 'k'
plt.rcParams['axes.linewidth'] = 3
plt.rcParams['axes.grid'] = 'False'

plt.imshow(N, cmap='gray', clim=(-1,0))

from matplotlib2tikz import save as tikz_save
tikz_save('axis.tex')

The output should look like:

However, with matplotlib2tikz, it looks like: