How to format the y- or x-axis labels in a seaborn FacetGrid

Question

I want to format y-axis labels in a seaborn FacetGrid plot, with a number of decimals, and/or with some text added.

import seaborn as sns
import matplotlib.pyplot as plt
sns.set(style="ticks")

exercise = sns.load_dataset("exercise")

g = sns.catplot(x="time", y="pulse", hue="kind", col="diet", data=exercise)
#g.xaxis.set_major_formatter(ticker.FuncFormatter(lambda x, pos: '{:,.2f}'.format(x) + 'K'))
#g.set(xticks=['a','try',0.5])
g.yaxis.set_major_formatter(ticker.FuncFormatter(lambda x, pos: '{:,.2f}'.format(x) + 'K'))
plt.show()

Inspired from How to format seaborn/matplotlib axis tick labels from number to thousands or Millions? (125,436 to 125.4K)

ax.xaxis.set_major_formatter(ticker.FuncFormatter(lambda x, pos: '{:,.2f}'.format(x) + 'K'))

It results in the following error.

AttributeError: 'FacetGrid' object has no attribute 'xaxis'

Asymmetric

Answer 1

• xaxis and yaxis are attributes of the plot axes, for a seaborn.axisgrid.FacetGrid type.
  • In the linked answer, the type is matplotlib.axes._subplots.AxesSubplot
• p in the lambda expression is the tick label number.
• seaborn: Building structured multi-plot grids
• matplotlib: Creating multiple subplots
• Tested and working with the following versions:
  • matplotlib v3.3.4
  • seaborn v0.11.1

import pandas as pd
import seaborn as sns
import matplotlib.pyplot as plt
import matplotlib.ticker as tkr

sns.set(style="ticks")

# load data
exercise = sns.load_dataset("exercise")

# plot data
g = sns.catplot(x="time", y="pulse", hue="kind", col="diet", data=exercise)

# format the labels with f-strings
for ax in g.axes.flat:
    ax.yaxis.set_major_formatter(tkr.FuncFormatter(lambda y, p: f'{y:.2f}: Oh baby, baby'))
    ax.xaxis.set_major_formatter(tkr.FuncFormatter(lambda x, p: f'{x}: Is that your best'))

• As noted in a comment by Patrick FitzGerald, the following code, without using tkr.FuncFormatter, also works to generate the previous plot.
• See matplotlib.axis.Axis.set_major_formatter

# format the labels with f-strings
for ax in g.axes.flat:
    ax.yaxis.set_major_formatter(lambda y, p: f'{y:.2f}: Oh baby, baby')
    ax.xaxis.set_major_formatter(lambda x, p: f'{x}: Is that your best')

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