Bug summary
ax.hist ignores lw argument. Must use linewidth in order to change the thickness of the lines.
Code for reproduction
# Test of lw vs linewidth in histograms
histogram1 = [1]
histogram2 = [3]
histogram3 = [5]
fig, ax = plt.subplots(figsize=(8, 8))
ax.hist(histogram1, bins=1, density=True, histtype='step', color='tab:blue', lw=1, label='lw=1')
ax.hist(histogram2, bins=1, density=True, histtype='step', color='tab:orange', lw=3, label='lw=3')
ax.hist(histogram3, bins=1, density=True, histtype='step', color='tab:green', linewidth=3, label='linewidth=3')
ax.legend()
plt.show()
print(matplotlib.__version__)
Actual outcome

Expected outcome
Using lw and linewidth produce same output.
Additional information
This was not a problem with an earlier version of Matplotlib (don't remember the version unfortunately, but definitely 3.x something).
Operating system
Ubuntu 24.04.2 LTS
Matplotlib Version
3.10.0
Matplotlib Backend
agg
Python version
3.12.3
Jupyter version
4.2.5
Installation
pip
Bug summary
ax.histignoreslwargument. Must uselinewidthin order to change the thickness of the lines.Code for reproduction
Actual outcome
Expected outcome
Using
lwandlinewidthproduce same output.Additional information
This was not a problem with an earlier version of Matplotlib (don't remember the version unfortunately, but definitely 3.x something).
Operating system
Ubuntu 24.04.2 LTS
Matplotlib Version
3.10.0
Matplotlib Backend
agg
Python version
3.12.3
Jupyter version
4.2.5
Installation
pip