Extended the convolution filter for correct dilation

[chbauman]

Changed the convolution filter from [1, 1] to [1, 1, 1] such that the mask is dilated on both sides, not only at the end.

PR Summary

PR Checklist

• [N/A] Has pytest style unit tests (and pytest passes).
• Is Flake 8 compliant (run flake8 on changed files to check).
• [N/A] New features are documented, with examples if plot related.
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• Conforms to Matplotlib style conventions (install flake8-docstrings and run flake8 --docstring-convention=all).
• [N/A] New features have an entry in doc/users/next_whats_new/ (follow instructions in README.rst there).
• [N/A] API changes documented in doc/api/next_api_changes/ (follow instructions in README.rst there).

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[jklymak]

Thanks for the PR. I can imagine this is correct. Do you have some examples showing the previous version did bad things and this is better?

[chbauman]

Hi, The following plots show the difference, they can be regeneratue using the given example (https://matplotlib.org/gallery/event_handling/resample.html) and setting ax.set_xlim <https://matplotlib.org/api/_as_gen/matplotlib.axes.Axes.set_xlim.html#matplotlib.axes.Axes.set_xlim>(232, 234) instead of ax.set_xlim <https://matplotlib.org/api/_as_gen/matplotlib.axes.Axes.set_xlim.html#matplotlib.axes.Axes.set_xlim> (16, 365). The first plot shows how it was before the PR and the second shows how it will be after. As you can see, the first plot seems to start somewhere at about 232.175, but actually the data is provided many timesteps before that (from x-range = 16 to ..) Therefore, it makes sense that the line would start before the first point that is shown in the first plot. This is all the PR is about, the extended convolution filter makes sure that the mask includes a point that lies before the shown x-range. [image: 1_1.png] [image: 1_1_1.png] Thanks for reviewing and have a nice weekend, Chris Am Fr., 15. Jan. 2021 um 16:30 Uhr schrieb Jody Klymak < notifications@github.com>:

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Thanks for the PR. I can imagine this is correct. Do you have some examples showing the previous version did bad things and this is better? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#19303 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AH5PD2VEBWT3YKPDDOTHDUDS2BNSRANCNFSM4WD4WNMA> .

[jklymak]

Your images didn't make it through via email.

[chbauman]

This should work I guess.

[chbauman]

The following plots show the difference, they can be regeneratue using the given example (https://matplotlib.org/gallery/event_handling/resample.html) and setting ax.set_xlim(232, 234) instead of ax.set_xlim(16, 365).
The top image shows how it was before, the one below shows how it looks with the proposed changes.

[jklymak]

Makes sense to me. Thanks a lot!