Bug summary

When adding the label position with the manual keyword, an IndexError is raised when using fewer levels than available in the contour.

Code for reproduction

# create random data
from matplotlib import pyplot as plt
import numpy as np
fig, ax = plt.subplots()
len_data = 10000
xs = np.random.normal(0, 1, len_data)
ys = np.random.normal(0, 1, len_data)
hist, x_edges, y_edges = np.histogram2d(xs, ys, bins=20)
Xc = 0.5 * (x_edges[:-1] + x_edges[1:])
Yc = 0.5 * (y_edges[:-1] + y_edges[1:])
flat = hist.flatten()
order = np.argsort(flat)[::-1]
cumsum = np.cumsum(flat[order])
cumsum/=cumsum[-1]

# compute contour levels
prob_levels = [0.95, 0.5]
clevels=[flat[order][np.searchsorted(cumsum, p)] for p in prob_levels]

#plot contour
contour = ax.contour(Xc, Yc, hist.T,levels = clevels)
ax.clabel(contour, levels= [clevels[-1]], fmt = {clevels[-1]: 'Label'},  inline=True, fontsize=ax.xaxis.label.get_size(), manual = [(1, 0.5)])

plt.show()

Actual outcome

line 22, in
ax.clabel(contour, levels= [clevels[-1]], fmt = {clevels[-1]: 'Label'}, inline=True, fontsize=ax.xaxis.label.get_size(), manual = [(1, 0.5)])
File "/home/.conda/envs/test_env/lib/python3.12/site-packages/matplotlib/axes/_axes.py", line 6697, in clabel
return CS.clabel(levels, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/.conda/envs/test_env/lib/python3.12/site-packages/matplotlib/contour.py", line 195, in clabel
self.add_label_near(x, y, inline, inline_spacing)
File "/home/.conda/envs/test_env/lib/python3.12/site-packages/matplotlib/contour.py", line 562, in add_label_near
self.add_label(*proj, rotation, self.labelLevelList[idx_level_min],
~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^
IndexError: list index out of range

Expected outcome

A contour label should be created only on the inner `contour```

Additional information

This seems to be due to this line, where self.add_label(*proj, rotation, self.labelLevelList[idx_level_min], self.labelCValueList[idx_level_min])
should rather be self.add_label(*proj, rotation, self.labelLevelList[level], self.labelCValueList[level])

Operating system

Ubuntu

Matplotlib Version

3.10.6

Matplotlib Backend

No response

Python version

3.12

Jupyter version

No response

Installation

None