[FIXED] How can I randomly apply rotation and flip to arrays in a list of using python?

Issue

I have a list of NumPy arrays, I want to apply rot90 and flip function randomly on it. So that in the end, I have a list where some arrays are as it is, and some are modified (with that two fuctions).

I directly pass that list of arrays to numpy.random.choice, it gives me the following error ValueError: a must be 1-dimensional.

thanks in advance.

Solution

One approach it to create a population of functions and pick randomly, using random.choice, the one to apply to each image:

import random
import numpy as np

# for reproducibility
random.seed(42)
np.random.seed(42)

# toy data representing the list of images
images = [np.random.randint(255, size=(128, 128)) for _ in range(10)]

functions = [lambda x: x, np.rot90, np.flip]

# pick function at random at apply to image
res = [random.choice(functions)(image) for image in images]

Answered By - Dani Mesejo