Random Walk(Python Crash Course) stuck in what seems to be a loop

Question

I am working through the Python Crash Course book and I don't know how to fix a problem with the Random Walk part. When I run the code, the command prompt gets stuck in a "processing" mode" which I cannot leave unless I close the window, i.e.

At first I thought that maybe I made the path too long but the code doesn't seem to work even if it is just 5 steps.

Here is the code for the class RandomWalk:

    from random import choice
    class RandomWalk():
    """A class to generate random walks."""

    def __init__(self,num_points=5):
        """Initialize attributes of a walk"""
        self.num_points = num_points

        #All walks start at (0,0).
        self.x_values = [0]
        self.y_values = [0]

    def fill_walk(self):
        """"Calculate all the points in the walk"""

        #Keep taking steps until the walk reaches the desired length
        while len(self.x_values) < self.num_points:
        #Decide which direction to go and how far to go there
            x_direction = choice([1,-1])
            x_distance = choice([0,1,2,3,4])
            x_step  = x_direction * x_distance

            y_direction = choice([1,-1])
            y_distance = choice([0,1,2,3,4])
            y_step = y_direction * y_distance

        #Reject moves that go nowhere
            if x_step == 0 and y_step == 0:
                continue

        #Calculate the next x and y values
        next_x = self.x_values[-1] + x_step
        next_y = self.y_values[-1] + y_step

        self.x_values.append(next_x)
        self.y_values.append(next_y)

Here is the code to run RandomWalk:

import matplotlib.pyplot as plt

from random_walk import RandomWalk

#Make a random walk, and plot the points.

rw = RandomWalk(5)
rw.fill_walk()

plt.scatter(rw.x_values, rw.y_values, s=15)
plt(show)

I would expect the result of the code to be a matplot view that shows me a random 5 steps walk.

Thanks for any help!

Answer 1

You never update x_values or num_points in your while loop so you create an infinite loop.

I think you missed a tab on the last lines of the RandomWalk class