This works. A big array of eight bit random numbers is constructed:

import numpy as np

spectrumArray = np.random.randint(0,255, (2**20,2**12)).astype(np.uint8)



This fails. It eats up all 64GBy of RAM:

spectrumArray = np.random.randint(0,255, (2**21,2**12)).astype(np.uint8)

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