Hands-on exercise – NumPy Arrays

Put the lesson NumPy Arrays into practice by writing a program yourself.

Exercise field

A table of hardness readings

The problem

Three samples were each tested for hardness at four positions along their length. Each row of the table below is one sample and each column is one position.

Store the table as a 2D NumPy array and select parts of it.

Your program should

Create a 2D array from the list of lists in the starter code.
Print its shape.
Print all readings for the second sample (row index 1).
Print the reading at the last position for every sample (the last column).

Expected output

(3, 4)
[201 198 205 199]
[149 199 176]

Your solution

Write your program below and press Run. Each run is checked against the expected output.

main.py

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Output

Press Run to see what your program prints.

Need help?

One possible solution. Other programs that print the same output are correct too.

solution.py

import numpy as npreadings = [    [152, 160, 158, 149],    [201, 198, 205, 199],    [175, 172, 178, 176],]hardness = np.array(readings)print(hardness.shape)print(hardness[1])print(hardness[:, -1])

Output

(3, 4) [201 198 205 199] [149 199 176]