BUG: _repr_latex is called in jupyter qtconsole

[chris-b1]

xref #11778

[jreback]

hmm, is this on master?

[jorisvandenbossche]

There are some issues at IPython/Jupyter for this: spyder-ide/qtconsole#65, spyder-ide/qtconsole#56 (IRkernel has the same problem for the display of their dataframes)

@chris-b1 Would you be able to test if this is solved in qtconsole master?

[jorisvandenbossche]

I think this is a reason to consider reverting #11778

[jreback]

cc @nbonnotte

[jorisvandenbossche]

Or, another option is making the use of the _repr_latex_ optional, and defaulting to False. So somebody who wants this feature for nbconvert, can switch it on, but knowing that it will bug in qtconsole.

[jreback]

so we could have an option display.latex.repr=False maybe?

[chris-b1]

Yeah, this also happens on qtconsole master. If there was a way to make this in_qtconsole check work again, that'd be a way to avoid an option.

But since they've restructured all the ipython/jupyter stuff, I don't know how (if it's possible) to do that.

[nbonnotte]

This goes beyond my current use of pandas or jupyter, so I'm not really qualified to say anything.

That being said, I like the idea of being able to nicely export my notebooks containing dataframes to LaTeX. And, if I understand correctly, this is more a bug of the jupyter qtconsole rather than pandas, right? So, if anything, my current understanding of the situation does not convince me that reverting #11778 is absolutely necessary. But maybe it's just because I use jupyter notebooks, and I feel closer to exporting them to LaTeX rather than using the qtconsole.

[jorisvandenbossche]

And, if I understand correctly, this is more a bug of the jupyter qtconsole rather than pandas, right? So, if anything, my current understanding of the situation does not convince me that reverting #11778 is absolutely necessary. But maybe it's just because I use jupyter notebooks

The qtconsole is used in eg Spyder, which I suppose quite some pandas users will use.
To be clear, ideally we find another solution or workaround so reverting #11778 is not needed. But if not, we cannot ship pandas like this in any case, as it would break the interactive usage for lots of users.

[jorisvandenbossche]

A possible idea is to do something similar as what sympy does, so that the user has to call a function to activate the latex repr support (sympy.init_printing()).
E.g. a pd.options.display.init_latex_repr() (although this being a function is not really consistent with the other options). Calling the function would then add the _repr_latex_ method to DataFrame on the fly.