Violin plots?

[olgabot]

Besides boxplots, another way to look at the distribution of data is by violin plots:

http://nbviewer.ipython.org/gist/olgabot/7902901

I'd like to add this to pandas. Is there interest in these plots? It currently depends on my prettyplotlib but that can be removed. My concern is that it depends on scipy.stats.gaussian_kde - is that fine?

[TomAugspurger]

Statsmodels has them. I think the idea is to keep the more statistical things there/maybe move some pandas stats functionality over.

[hayd]

These look fun! I think that dep is fine (similar to elsewhere in codebase: https://github.com/pydata/pandas/blob/0327addef295fef292f2fdf8c95546c4cc039abb/pandas/tools/rplot.py#L528)

Edit: I posted this before seeing @TomAugspurger's comment...

[jtratner]

except that the rplot module isn't very well maintained and is quite slow.

[olgabot]

Ah yes statsmodels. I looked at it but didn't end up using them because you couldn't specify the kernel bandwidth.Theirs is quite nice because you can do the left/right distributions for direct comparisons. Maybe I'll just add a PR there that adds a bandwidth specification to the args.

[jtratner]

If they already have some of this, probably better to move it to there
instead. Statsmodels has pandas as a dep so you can still use pandas stuff.

Note that rplot, in retrospect, was a controversial merge precisely for the reason @TomAugspurger mentioned.
So that's indeed the guideline we've tried (or should have) to stick to in the past.

@jtratner , yep, it was in PR limbo for the longest while and I wasn't aware of the statsmodels issue
which is why I prodded for it's merge. It was, in fairness, a sizeable piece of code to contribute. #2015, statsmodels/statsmodels#692

[olgabot]

Okay great! I'll stick to statsmodels for the violinplots. Should other stuff like the clustergrams/clustered heatmaps also be there?

It's a fuzzy boundary. The plots are beautiful but are far more bespoke then pandas' current meat
and potatoes stance, they do stick out a bit among the plaid and denim.

We might call them "2nd order plots" maybe? :)

[jreback]

maybe its worthwhile to refactor out these secondary plots from both pandas and statsmodels and make a common import? (so in effect available in both, but not code dupe)

Where's the all-singing, all-dancing pydata exploratory data viz library??

[olgabot]

pydataviz? aka every data analyst's ipython notebook and codebase...

[dragoljub]

I'm hoping https://github.com/vispy/vispy will be the beginning of such a plotting library. Plotting 100M points a second with a GPU beats the 25 seconds plus it takes for matplotlib right now. 😄

@olgabot, I see ggplot2 supports these plots as a distinct geom, would be nice to have these
available in http://github.com/yhat/ggplot. I'm rooting for them.

cc @JanSchulz