fix .hvplot for ibis

[MarcSkovMadsen]

Closes #988

After this change I can produce a plot from the example in #988. But it seems it does not understand the Timestamp type should be shown as datetime on the x-axis. I will create a separate issue with holoviews for that.

I've created an issue here holoviz/holoviews#5521.

[philippjfr]

Looks good to me!

[philippjfr]

Really appreciate you looking into this. The ibis backend was left in a half-finished state when the folks working on it ran out of funding. So reviving it is pretty exciting and if we can make it work well let's write a blog post about it.

[MarcSkovMadsen]

Thanks. Does that mean you will now approve and merge @philippjfr ?

[philippjfr]

Was giving Maxime a chance to review but I'll just go ahead and merge now.

[maximlt]

Sorry it's been a short and busy week.

Thanks Marc for working on that. I will just say that personally I don't consider that as a priority as Ibis was never advertised in hvPlot, my focus is rather on stability/bug fixes and docs.

A couple of comments on that specific PR:

• its title isn't very explicit, it looks like everything has been fixed :)
• the if statement should have a comment that explains why hasattr(data.columns, 'name') is required (I do not know why ibis doesn't have the same interface as Pandas'). The general lack of comments make the converter difficult to apprehend.
• In the test file the try/except block should try to catch ImportError
• In the test file importing pandas shouldn't be in the try/except block as pandas is a dependency of hvPlot so ensured to be always there when the test suite is executed
• ibis is not installed so these new tests will never run. HoloViews does install ibis part to run its test suite. It actually was a bit of a pain to get it to installed with conda, that wouldn't solve for ibis-framework (Cannot install on Linux conda-forge/ibis-framework-feedstock#54) so we mapped it to ibis-sqlite for conda but kept ibis-framework for PyPI. Maybe this can be revisited now.

[maximlt]

@MarcSkovMadsen which version of ibis did you you? How did you install it?

[MarcSkovMadsen]

pip install ibis-framework and pip install ibis-framework[duckdb]. Version 3.2.0.

[MarcSkovMadsen]

Thanks. Should I update try/ except across the files? I saw what was in other files and copied that.

This is another example

Those wrong imports are all over the place in the code.

[MarcSkovMadsen]

Regarding the title. When I wrote it, I thought HoloViews was supporting Ibis well and this was just a small thing and then ibis would work well with hvplot. Now I can see that is far from the situation.