How to plot pandas kde with a horizontal orientation

Question

Pandas offers kind='kde' when plotting. In my setting, I would prefer a kde density. The alternative kind='histogram' offers the orientation option: orientation='horizontal', which is strictly necessary for what I am doing. Unfortunately, orientation is not available for kde.

At least this is what I think that happens because I get a

in set_lineprops
    raise TypeError('There is no line property "%s"' % key)
TypeError: There is no line property "orientation"

Is there any straight forward alternative for plotting kde horizontally as easily as it can be done for histogram?

import matplotlib.pyplot as plt
import numpy as np
import pandas as pd

plt.ion()

ser = pd.Series(np.random.random(1000))
ax1 = plt.subplot(2,2,1)
ser.plot(ax = ax1, kind = 'hist')
ax2 = plt.subplot(2,2,2)
ser.plot(ax = ax2, kind = 'kde')
ax3 = plt.subplot(2,2,3)
ser.plot(ax = ax3, kind = 'hist', orientation = 'horizontal')

# not working lines below
ax4 = plt.subplot(2,2,4)
ser.plot(ax = ax4, kind = 'kde', orientation = 'horizontal')

Trenton McKinney · Answer 1 · 2022-07-01T16:54:49.117

Adding previously deleted answer as a community wiki because it's a helpful answer.
pandas.Series.plot.kde does not have an option to change the orientation of the plot.
Use scipy.stats.gaussian_kde to calculate the values, and plot them on a line with matplotlib.axes.Axes.plot.
Alternatively, seaborn.kdeplot is an option.
gaussian_kde is used under the hood by both .plot.kde and sns.kdeplot

import pandas as pd
import numpy as np
import seaborn as sns
from scipy.stats import gaussian_kde

# crate subplots and don't share x and y axis ranges
fig, axes = plt.subplots(2, 2, figsize=(10, 10), sharex=False, sharey=False)

# flatten the axes for easy selection from a 1d array
axes = axes.flat

# create sample data
np.random.seed(2022)
ser = pd.Series(np.random.random(1000)).sort_values()

# plot example plots
ser.plot(ax=axes[0], kind='hist', ec='k')
ser.plot(ax=axes[1], kind='kde')
ser.plot(ax=axes[2], kind='hist', orientation='horizontal', ec='k')

# 1. create kde model
gkde = gaussian_kde(ser)

# 2. create a linspace to match the range over which the kde model is plotted
xmin, xmax = ax2.get_xlim()
x = np.linspace(xmin, xmax, 1000)

# 3. plot the values
axes[3].plot(gkde(x), x)

# Alternatively, use seaborn.kdeplot and skip 1., 2., and 3.
# sns.kdeplot(y=ser, ax=axes[3])

How to plot pandas kde with a horizontal orientation

1 Answers1