Add colorbars to plots of gallery and tutorial examples

[yvonnefroehlich]

Description of proposed changes
This PR aims to add colorbars to some plots of the gallery and tutorial examples:

• Creating a map with contour lines (contour_map.py)
• Sampling along tracks (track_sampling.py)
• Plotting a surface (grdview_surface.py)

Fixes #2030

Reminders

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• Add tests for new features or tests that would have caught the bug that you're fixing.
• Add new public functions/methods/classes to doc/api/index.rst.
• Write detailed docstrings for all functions/methods.
• If wrapping a new module, open a 'Wrap new GMT module' issue and submit reasonably-sized PRs.
• If adding new functionality, add an example to docstrings or tutorials.

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[yvonnefroehlich]

I extended issue #2030 and added also to Plotting a surface a colorbar. Furthermore, I added a grid. Of course, we can discuss these changes!

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Strictly speaking, two colorbars have to be added to Sampling along tracks, as there are color-codings for both the bathymetry ("gray") and the sampled bathymetry points ("terra"). Should I add both colorbars or only the one for the sampled bathymetry points?

[seisman]

I extended issue #2030 and added also to Plotting a surface a colorbar. Furthermore, I added a grid. Of course, we can discuss these changes!

Adding the grid looks good to me.

Strictly speaking, two colorbars have to be added to Sampling along tracks, as there are color-codings for both the bathymetry ("gray") and the sampled bathymetry points ("terra"). Should I add both colorbars or only the one for the sampled bathymetry points?

Yes, two colorbars makes more sense. It's also a good example to show how to add two colorbars on the same map.

[seisman]

@yvonnefroehlich Thanks for your active contributions to the PyGMT project. On behalf of the PyGMT maintainers @GenericMappingTools/pygmt-maintainers, I’d like to invite you to join the “PyGMT Devs” Slack channel, which is used usually for some internal discussions. Please leave your email address here or send your email address to me (seisman.info#gmail.com) if you’d like to join.

[yvonnefroehlich]

@yvonnefroehlich Thanks for your active contributions to the PyGMT project. On behalf of the PyGMT maintainers @GenericMappingTools/pygmt-maintainers, I’d like to invite you to join the “PyGMT Devs” Slack channel, which is used usually for some internal discussions. Please leave your email address here or send your email address to me (seisman.info#gmail.com) if you’d like to join.

Thanks @GenericMappingTools/gmt-maintainers for this positive feedback 🙂!
I would be pleased to join the "PyGMT Devs" Slack channel. @seisman I send you my email address via email.
Hope I can add some useful thoughts to the discussions 😉.

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I am sorry for accidentally closing this PR.

[yvonnefroehlich]

Hm. Maybe it would be fair to ask @weiji14 whether he is fine with the changes of track_sampling.py as he is the original author of this example? But not sure if he is currently available 🙂.
Edit: I think three approving reviewers should be enough for merging.

[weiji14]

Hm. Maybe it would be fair to ask @weiji14 whether he is fine with the changes of track_sampling.py as he is the original author of this example? But not sure if he is currently available slightly_smiling_face. Edit: I think three approving reviewers should be enough for merging.

Sorry for the late response. The original intention of the track_sampling.py gallery example added in #308 was to showcase the grdtrack data processing function, rather than as a proper 'map' per se.

Personally, I feel that having just one colorbar (the normalized elevation one) would be enough, since the background grayscale earth_relief elevation is just for context. But I also find normalized elevation to be hard to interpret (see my comment below), so not sure what's a good plan forward 😅 What are your thoughts?

[seisman]

The original intention of the track_sampling.py gallery example added in #308 was to showcase the grdtrack data processing function, rather than as a proper 'map' per se.

Personally, I feel that having just one colorbar (the normalized elevation one) would be enough, since the background grayscale earth_relief elevation is just for context. But I also find normalized elevation to be hard to interpret (see my comment below), so not sure what's a good plan forward 😅 What are your thoughts?

Perhaps we can rewrite the grdtrack example to something like (https://docs.gmt-china.org/latest/examples/ex026/):

[weiji14]

Perhaps we can rewrite the grdtrack example to something like (https://docs.gmt-china.org/latest/examples/ex026/)

Yes, how about we revert the changes to track_sampling and redesign the example in a separate PR? I think the other changes that add a colorbar are good to go.

[yvonnefroehlich]

Perhaps we can rewrite the grdtrack example to something like (https://docs.gmt-china.org/latest/examples/ex026/)

Yes, how about we revert the changes to track_sampling and redesign the example in a separate PR? I think the other changes that add a colorbar are good to go.

That's fine with me.

[seisman]

Perhaps we can rewrite the grdtrack example to something like (docs.gmt-china.org/latest/examples/ex026)

Yes, how about we revert the changes to track_sampling and redesign the example in a separate PR? I think the other changes that add a colorbar are good to go.

Sounds good.

[yvonnefroehlich]

I reverted the changes of track_sampling.py via commit ad2bd79.

[weiji14]

Thanks @yvonnefroehlich, and sorry for the back and forth 🙂