如何注释 seaborn pairplots

Question

I have a collection of binned data from which I generate a series of seaborn pairplots. Since all of the bins have the same labels, but not bin names, I need to annotate the pairplots with the bin name 'n' below so that I can later associate them with their bins.

import seaborn as sns
groups = data.groupby(pd.cut(data['Lat'], bins))
for n,g in groups:
    p = sns.pairplot(data=g, hue="Label", palette="Set2", 
                 diag_kind="kde", size=4, vars=labels)

I noted in the documentation that seaborn uses, or is built upon, matplotlib. I have been unable to figure out how to annotate the legend on the left, or provide a title above or below the paired plots. Can anyone provide examples of pointers to the documentation on how to add arbitrary text to those three areas of a plot?

Answer 1

After following up on mwaskom's suggestion to use matplotlib.text() (thanks), I was able to get the following to work as expected:

p = sns.pairplot(data=g, hue="Label", palette="Set2", 
             diag_kind="kde", size=4, vars=labels)
#bottom labels
p.fig.text(0.33, -0.01, "Bin: %s"%(n), ha ='left', fontsize = 15)
p.fig.text(0.33, -0.04, "Num Points: %d"%(len(g)), ha ='left', fontsize = 15)

and other useful functionality:

# title on top center of subplot
p.fig.suptitle('this is the figure title', verticalalignment='top', fontsize=20)

# title above plot
p.fig.text(0.33, 1.02,'Above the plot', fontsize=20)

# left and right of plot
p.fig.text(0, 1,'Left the plot', fontsize=20, rotation=90)
p.fig.text(1.02, 1,'Right the plot', fontsize=20, rotation=270)

# an example of a multi-line footnote
p.fig.text(0.1, -0.08,
     'Some multiline\n'
     'footnote...',
      fontsize=10)

Answer 2

In addition, using the seaborn functionality, you can move the title up. After p=sns.pairplot , add

p.fig.suptitle("here is your title", y=1.05)

This title will be above the actual plot area instead of overlapping the plot.

You can also use fontweight (bold, etc) in addition to the fontsize.