Code Discrepancy Compared to Textbook

[Operations-Researcher-02]

I am working on implementing the first example in a book but for some reason I am getting a different answer even though I did not change any of the code. Do you see what I may be doing wrong? From the book:

And my code:

The outputs, which should be the same, are highlighted in blue. What could I be doing wrong?

 

[VBService]

Please provide the code using

and then

this make it easier to provide help to you.

 

[Operations-Researcher-02]

import numpy as np
m = 3
m2 = m ** 2
q = np.zeros(m2)
q[m2 // 2] = 1
def get_P(m, p_up, p_down, p_left, p_right):
    m2 = m ** 2
    P = np.zeros((m2, m2))
    ix_map = {i + 1: (i // m, i % m) for i in range(m2)}
    for i in range(m2):
        for j in range(m2):
            r1, c1 = ix_map[i + 1]
            r2, c2 = ix_map[j + 1]
            rdiff = r1 - r2
            cdiff = c1 - c2
            if rdiff == 0:
                if cdiff == 1:
                    P[i, j] = p_left
                elif cdiff == -1:
                    P[i, j] = p_right
                elif cdiff == 0:
                    if r1 == 0:
                        P[i, j] += p_down
                    elif r1 == m - 1:
                        P[i, j] += p_up
                    if c1 == 0:
                        P[i, j] += p_left
                    elif c1 == m - 1:
                        P[i, j] += p_right
                elif rdiff == 1:
                    if cdiff == 0:
                        P[i, j] = p_down
                elif rdiff == -1:
                    if cdiff == 0:
                        P[i, j] = p_up
    return P
P = get_P(3, 0.2, 0.3, 0.25, 0.25)
n = 1
Pn = np.linalg.matrix_power(P, n)
np.matmul(q, Pn)

 

[VBService]

IMO, your code is identical to the code from the book, so it seems the book shows an incorrect result.

 

[WhiteCube]

I do not understand your program (a few comments would be nice) but common sense is telling me that these 3 lines should have the same indentation.

if rdiff == 0:
elif rdiff == 1:
elif rdiff == -1: