Boxplot DemoΒΆ

Example boxplot code

import numpy as np
import matplotlib.pyplot as plt

# Fixing random state for reproducibility
np.random.seed(19680801)

# fake up some data
spread = np.random.rand(50) * 100
center = np.ones(25) * 50
flier_high = np.random.rand(10) * 100 + 100
flier_low = np.random.rand(10) * -100
data = np.concatenate((spread, center, flier_high, flier_low))
Basic Plot

Out:

{'whiskers': [<matplotlib.lines.Line2D object at 0x7f6a29281370>, <matplotlib.lines.Line2D object at 0x7f6a292815e0>], 'caps': [<matplotlib.lines.Line2D object at 0x7f6a29281460>, <matplotlib.lines.Line2D object at 0x7f6a292816a0>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f6a29281610>], 'medians': [<matplotlib.lines.Line2D object at 0x7f6a2930c220>], 'fliers': [<matplotlib.lines.Line2D object at 0x7f6a2930c070>], 'means': []}
fig2, ax2 = plt.subplots()
ax2.set_title('Notched boxes')
ax2.boxplot(data, notch=True)
Notched boxes

Out:

{'whiskers': [<matplotlib.lines.Line2D object at 0x7f6a296246d0>, <matplotlib.lines.Line2D object at 0x7f6a296241c0>], 'caps': [<matplotlib.lines.Line2D object at 0x7f6a2a0fe3d0>, <matplotlib.lines.Line2D object at 0x7f6a2a0feaf0>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f6a296240a0>], 'medians': [<matplotlib.lines.Line2D object at 0x7f6a293d7220>], 'fliers': [<matplotlib.lines.Line2D object at 0x7f6a293d7820>], 'means': []}
green_diamond = dict(markerfacecolor='g', marker='D')
fig3, ax3 = plt.subplots()
ax3.set_title('Changed Outlier Symbols')
ax3.boxplot(data, flierprops=green_diamond)
Changed Outlier Symbols

Out:

{'whiskers': [<matplotlib.lines.Line2D object at 0x7f6a29648160>, <matplotlib.lines.Line2D object at 0x7f6a29648580>], 'caps': [<matplotlib.lines.Line2D object at 0x7f6a296484c0>, <matplotlib.lines.Line2D object at 0x7f6a29ebcb80>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f6a297f55b0>], 'medians': [<matplotlib.lines.Line2D object at 0x7f6a29ebccd0>], 'fliers': [<matplotlib.lines.Line2D object at 0x7f6a29ebc0d0>], 'means': []}
fig4, ax4 = plt.subplots()
ax4.set_title('Hide Outlier Points')
ax4.boxplot(data, showfliers=False)
Hide Outlier Points

Out:

{'whiskers': [<matplotlib.lines.Line2D object at 0x7f6a29462850>, <matplotlib.lines.Line2D object at 0x7f6a294625e0>], 'caps': [<matplotlib.lines.Line2D object at 0x7f6a29462af0>, <matplotlib.lines.Line2D object at 0x7f6a29462d60>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f6a29462190>], 'medians': [<matplotlib.lines.Line2D object at 0x7f6a2cb638b0>], 'fliers': [], 'means': []}
red_square = dict(markerfacecolor='r', marker='s')
fig5, ax5 = plt.subplots()
ax5.set_title('Horizontal Boxes')
ax5.boxplot(data, vert=False, flierprops=red_square)
Horizontal Boxes

Out:

{'whiskers': [<matplotlib.lines.Line2D object at 0x7f6a2a119220>, <matplotlib.lines.Line2D object at 0x7f6a2a119c40>], 'caps': [<matplotlib.lines.Line2D object at 0x7f6a2896c100>, <matplotlib.lines.Line2D object at 0x7f6a2cb891c0>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f6a2a477ca0>], 'medians': [<matplotlib.lines.Line2D object at 0x7f6a29628c40>], 'fliers': [<matplotlib.lines.Line2D object at 0x7f6a29628790>], 'means': []}
fig6, ax6 = plt.subplots()
ax6.set_title('Shorter Whisker Length')
ax6.boxplot(data, flierprops=red_square, vert=False, whis=0.75)
Shorter Whisker Length

Out:

{'whiskers': [<matplotlib.lines.Line2D object at 0x7f6a2960d760>, <matplotlib.lines.Line2D object at 0x7f6a2960da30>], 'caps': [<matplotlib.lines.Line2D object at 0x7f6a2960dd00>, <matplotlib.lines.Line2D object at 0x7f6a2960dfd0>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f6a2960d490>], 'medians': [<matplotlib.lines.Line2D object at 0x7f6a296172e0>], 'fliers': [<matplotlib.lines.Line2D object at 0x7f6a296175b0>], 'means': []}

Fake up some more data

Making a 2-D array only works if all the columns are the same length. If they are not, then use a list instead. This is actually more efficient because boxplot converts a 2-D array into a list of vectors internally anyway.

data = [data, d2, d2[::2]]
fig7, ax7 = plt.subplots()
ax7.set_title('Multiple Samples with Different sizes')
ax7.boxplot(data)

plt.show()
Multiple Samples with Different sizes

References

The use of the following functions, methods, classes and modules is shown in this example:

Total running time of the script: ( 0 minutes 5.433 seconds)

Keywords: matplotlib code example, codex, python plot, pyplot Gallery generated by Sphinx-Gallery