Repository navigation
Hexbin mincnt parameter docstring should say "more than or equal to" not "more than" #16865
Description
The current docstring for hexbin has this for mincnt:
mincnt : int > 0, default: *None*
If not *None*, only display cells with more than *mincnt*
number of points in the cell.But, it really displays cells that have more than or equal to mincnt.
The int > 0 is also slightly confusing. It does accept 0 and negative numbers and can appear to relate to the 'more than' below when it does not.
Activity
anntzer commentedon Mar 21, 2020
There's also the problem that when C is None, the condition is >= mincnt (as you write), but when C is not None, the condition is > mincnt (as documented). Perhaps this should be made consistent first? (I think >= mincnt makes more sense?)
tdpetrou commentedon Mar 21, 2020
Agreed, consistency should be done first. >= makes more sense to me as well as it is a minimum count.
anntzer commentedon Mar 21, 2020
Actually, looking at this again, I think I see why it's > for the case with a reducer: with the effective mincnt default of 0 (None is converted to 0), we don't want to get a warning with np.mean(empty_list), but just get nan straight away (at least np.mean([]) returns nan with a warning, but np.max() would be even worse as it raises an exception).
On the other hand, in the case without C, it makes sense to keep empty cells mapped, well, to zero.
Not sure if there's an easy way out there...
RebeccaWPerry commentedon Oct 25, 2021
Why is the default to set mincnt to 0 instead of 1? Would someone want to run a reduce function on a cell containing 0 points? As documented, mincnt must be greater than 0 (mincnt : int > 0), so it seems counterintuitive that the code sets it to 0.
anntzer commentedon Oct 25, 2021
Briefly looking at this again, I think that
So mincnt has two slightly different semantics in both cases. Perhaps yet another solution would be to note that mincnt is actually not so useful in the case of C being unset: in that case, the empty bins can just be reported as zero, and if you want to mask them out you can do so using standard colormapping tools (e.g.,
vmin=1andcmap=mpl.cm.get_cmap().with_extremes(under="none")). So perhaps one should just deprecate the use of mincnt together with C unset? I'm not really sure what the history behindmincntis... (unfortunately the git log is not helpful here)github-actions commentedon Jul 14, 2023
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!
anntzer commentedon Aug 15, 2023
#26113 (comment) is likely still a problem for now.