Colormaps alter your perception

Here I plot the function

\[f(x, y) = \sin(x) + \cos(y)\]

with different colormaps.

import numpy as np
import matplotlib.pyplot as plt

x = np.linspace(-np.pi, np.pi, 300)
xx, yy = np.meshgrid(x, x)
z = np.cos(xx) + np.cos(yy)

plt.figure()
plt.imshow(z)

plt.figure()
plt.imshow(z, cmap=plt.cm.get_cmap('hot'))

plt.figure()
plt.imshow(z, cmap=plt.cm.get_cmap('Spectral'),
           interpolation='none')

# Not needed for the Gallery.
# Only for direct execution
plt.show()

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You can define blocks in your source code with interleaving prose.

print(("This writes to stdout and will be",
      " displayed in the HTML file"))

Out:

('This writes to stdout and will be', ' displayed in the HTML file')