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1. oscargus commented on Jul 29, 2022

   

   oscargus

   on Jul 29, 2022

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   Indeed! If anything, the bottom subplot should expand. Definitely not the top one.
2. oscargus

   added

   topic: color/colorbar

   on Jul 29, 2022
3. oscargus commented on Jul 29, 2022

   

   oscargus

   on Jul 29, 2022

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   The problem seems to be that
   

   matplotlib/lib/matplotlib/colorbar.py

   Line 1087 in 1bac3b3

   ax = self.mappable.axes

   
   points at the wrong axis, i.e. the top one. Which leads to that the rest of the code is applied to the top rather than the bottom axis.
   

   matplotlib/lib/matplotlib/colorbar.py

   Lines 1090 to 1099 in 1bac3b3

   	try:
   	gs = ax.get_subplotspec().get_gridspec()
   	subplotspec = gs.get_topmost_subplotspec()
   	except AttributeError:
   	# use_gridspec was False
   	pos = ax.get_position(original=True)
   	ax._set_position(pos)
   	else:
   	# use_gridspec was True
   	ax.set_subplotspec(subplotspec)

   So self.mappable.axes is not set correctly(?).
4. oscargus commented on Jul 29, 2022

   

   oscargus

   on Jul 29, 2022

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   It is set correctly, it is "just" that the logic doesn't consider this case.

   The code assumes that the mappable provided (the scatter plot) is also the object that got the colorbar attached to it and therefore the part that should be updated when the colorbar is removed. Probably one should use ax instead here. (Althiguh that may cause other issues...)
5. jklymak commented on Jul 29, 2022

   

   jklymak

   on Jul 29, 2022

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   Thanks @oscargus that does indeed seem to be the problem. I'm skeptical we should resize anything, but if that is the existing behaviour we should be storing the result of ax=ax and operating on that (if it is a single axes).

   The problem is that the colorbar axes is created outside of colorbar, so the colorbar method never knows if it stole from space anyone or not. I think its overreach for colorbar to then try to give space back...

   Reacted by Tim Hoffmann
6. jklymak commented on Dec 11, 2022

   

   jklymak

   on Dec 11, 2022

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   Just to clarify here:

   import matplotlib.pyplot as plt
   
   fig, ax = plt.subplots(2, layout='constrained')
   s = ax[0].scatter([0, 1, 2], [0, 1, 2], c=[0, 1, 2])
   plt.colorbar(s, ax=ax[0])
   
   plt.show()

   Does what I think the OP wants.

   If they really don't want to use constrained layout, they can also do various other hacks (inset_axes is the best way), or make a mock scalarmappable

   fig, ax = plt.subplots(2)
   s = ax[0].scatter([0, 1, 2], [0, 1, 2], c=[0, 1, 2])
   plt.colorbar(s, ax=ax[0])
   cbar = plt.colorbar(mpl.cm.ScalarMappable(norm=plt.Normalize(), cmap=plt.get_cmap('RdBu_r')),
   ax=ax[1])
   cbar.remove()
7. github-actions commented on Feb 2, 2026

   

   github-actionsBot

   on Feb 2, 2026 – with GitHub Actions

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   This issue has been marked "inactive" because it has been 365 days since the last comment. If this issue is still present in recent Matplotlib releases, or the feature request is still wanted, please leave a comment and this label will be removed. If there are no updates in another 30 days, this issue will be automatically closed, but you are free to re-open or create a new issue if needed. We value issue reports, and this procedure is meant to help us resurface and prioritize issues that have not been addressed yet, not make them disappear. Thanks for your help!
8. github-actions

   added

   status: inactiveMarked by the “Stale” Github ActionMarked by the “Stale” Github Action

   on Feb 2, 2026
9. timhoffm commented on Feb 2, 2026

   

   timhoffm

   on Feb 2, 2026

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   Duplicate #22257
10. timhoffm

    closed this as a duplicateof [Bug]: colorbar.remove() does not always work #22257 on Feb 2, 2026
11. QuLogic

    removed

    status: inactiveMarked by the “Stale” Github ActionMarked by the “Stale” Github Action

    on Feb 4, 2026