I want to map each numpy array to a color to create an image.
For example: if I have the numpy array:
[ [0 0 1 3]
[0 2 4 5]
[1 2 3 6] ]
I want to make an image by mapping all values below 3 to blue like
[ [blue blue sky-blue green]
[blue sky-blue green green]
[blue sky-blue green green]
You can make a two-color color map. Then make an array with 1 or 0 depending on your condition and pass both to pyplot.imshow():
import numpy as np
from matplotlib import pyplot as plt
from matplotlib.colors import ListedColormap
# white and blue
color = ListedColormap([(1,1,1), (0,0,1)])
a = np.array([
[0, 0, 1, 3],
[0, 2, 4, 5],
[1, 2, 3, 6]
])
plt.axis('off')
plt.imshow(a < 3, cmap=color)
