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 0x7f90b3f9d940>, <matplotlib.lines.Line2D object at 0x7f90b3f9dd60>], 'caps': [<matplotlib.lines.Line2D object at 0x7f90b3f9d2e0>, <matplotlib.lines.Line2D object at 0x7f90b3f9db50>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f90b3f34970>], 'medians': [<matplotlib.lines.Line2D object at 0x7f90b3f9d9d0>], 'fliers': [<matplotlib.lines.Line2D object at 0x7f90b4b87940>], 'means': []}
fig2, ax2 = plt.subplots()
ax2.set_title('Notched boxes')
ax2.boxplot(data, notch=True)
Notched boxes

Out:

{'whiskers': [<matplotlib.lines.Line2D object at 0x7f90b3de16d0>, <matplotlib.lines.Line2D object at 0x7f90b3fc2370>], 'caps': [<matplotlib.lines.Line2D object at 0x7f90b3fc2c10>, <matplotlib.lines.Line2D object at 0x7f90b3fc24c0>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f90b3de1cd0>], 'medians': [<matplotlib.lines.Line2D object at 0x7f90b3fc26a0>], 'fliers': [<matplotlib.lines.Line2D object at 0x7f90b3fc2e50>], '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 0x7f90b5a838e0>, <matplotlib.lines.Line2D object at 0x7f90b5a83700>], 'caps': [<matplotlib.lines.Line2D object at 0x7f90b59e7760>, <matplotlib.lines.Line2D object at 0x7f90b408d6d0>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f90b56fdd60>], 'medians': [<matplotlib.lines.Line2D object at 0x7f90b3e8f610>], 'fliers': [<matplotlib.lines.Line2D object at 0x7f90b3e8f1c0>], '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 0x7f90b50ae370>, <matplotlib.lines.Line2D object at 0x7f90b5a748e0>], 'caps': [<matplotlib.lines.Line2D object at 0x7f90b3e142e0>, <matplotlib.lines.Line2D object at 0x7f90b3e14760>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f90b47240d0>], 'medians': [<matplotlib.lines.Line2D object at 0x7f90b3e14040>], '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 0x7f90b3f9c580>, <matplotlib.lines.Line2D object at 0x7f90b3f9c850>], 'caps': [<matplotlib.lines.Line2D object at 0x7f90b3f9cb20>, <matplotlib.lines.Line2D object at 0x7f90b3f9cdf0>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f90b3f9c2b0>], 'medians': [<matplotlib.lines.Line2D object at 0x7f90b3f96100>], 'fliers': [<matplotlib.lines.Line2D object at 0x7f90b3f963d0>], '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 0x7f90b3fced90>, <matplotlib.lines.Line2D object at 0x7f90b3d340a0>], 'caps': [<matplotlib.lines.Line2D object at 0x7f90b3d34370>, <matplotlib.lines.Line2D object at 0x7f90b3d34640>], 'boxes': [<matplotlib.lines.Line2D object at 0x7f90b3fceac0>], 'medians': [<matplotlib.lines.Line2D object at 0x7f90b3d34910>], 'fliers': [<matplotlib.lines.Line2D object at 0x7f90b3d34be0>], '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 1.378 seconds)

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