Write a code that makes a 2D square array with 20×20 elements. Fill the array with random numbers initially. Then, "draw" a square in the array by adding a value of 4 to those array elements, and plot it with imshow. The square should be centered and have side lengths of 10 .

Answer explained below. Python language used

Explanation:

The size of the square is of size 10. So assuming zero indexing,

vertical side1 (column Index = 5): row index from 5 to 14

vertical side1 (column Index = 14): row index from 5 to 14

horizontal side1 (row Index = 5): column index from 5 to 14

horizontal side2 (row Index = 14): column index from 5 to 14

Note:

while indexing, data_new[a:b,c] denotes,

row index: a to b-1

column index: c

Similarly data_new[a,b:c] denotes,

row index: a

column index: b to c-1

Code:

import matplotlib.pyplot as plt

import numpy as np

size_1 = 20

size_2 = 20

data_new = np.random.random((size_1,size_2))

data_new[5:15,5] = 4

data_new[5:15,14] = 4

data_new[5,5:15] = 4

data_new[14,5:15] = 4

fig = plt.figure(figsize=(10,10))

plt.imshow(data_new)

plt.colorbar()

plt.show()

1. b

2. c

3. b

4. a

5. b

i think so.

by: nicholas