Latex label compatibility issues while using Bokeh as backend

Describe the bug I want to use latex for my labels and so I use the following line of code.

import arviz.labels as azl
labeller = azl.MapLabeller(var_name_map={"Cxf": r"$\C_{xf}$","Cxr": r"$C_{xr}$"})
`

However, when I plot the posterior using “Bokeh” as backend using ax_post = az.plot_posterior(idata,backend = "Bokeh",figsize = (12,8),labeller=labeller) I get this

To Reproduce The bug can be reproduced with the attached data file and the above lines of code. https://drive.google.com/file/d/1Kld1u4VaGWYVz5Yq9GClUFaGDhFIfLhF/view?usp=sharing

Expected behavior This problem does not exist when I use matplotlib as my backend. See plots below

Additional context arviz version - 0.12.0 bokeh version - 2.4.2

[OriolAbril]

I think for latex in bokeh you need to use different delimiters like double dollar sign. Can you try it?

More info at https://docs.bokeh.org/en/2.4.3/docs/user_guide/styling.html#latex

[OriolAbril]

@agustinaarroyuelo and I (but mostly Agustina) investigated the issue. Bokeh 2.x only supports latex rendering on the elements explicitly listed in the documentation. That is:

(emphasis mine) Currently, you can use LaTeX and MathML notations with axis labels and tick labels using major_label_overrides(). You can also use LaTeX with div or paragraph widgets.

The examples in the docs restrict to these elements, but in your case you want to use latex rendering in a Title element, which doesn’t work.

This has already been fixed in the next release candidate for bokeh 3.0, at least for Title and Label elements (done in https://github.com/bokeh/bokeh/pull/11708), but as bokeh 3.0 is still at the release candidate stage, you’ll need to do pip install bokeh --pre to try it out. It is also a major version which probably has some backward incompatible changes, so some of the bokeh code in ArviZ might not work with it. I will be closing the issue as it is nothing to be fixed on our side, but feel free to let us know how it goes if you try this. We’ll test ArviZ with bokeh 3.0 once the api is final and a release is made.