Generate 2D random walk trajectory

random_walk_2d.py

import numpy as np

def walk(n):
    # check if the number of steps is an integer
    if int(n) != n:
        print('number of steps should be an integer')
        return None
    # the initial position is (0,0)
    xy_0 = np.array([0.0, 0.0])
    # generate displacements of each step
    dxdy = np.random.randn(int(n), 2)
    # cumulative sum displacement to get positions at each step
    xy = xy_0 + np.cumsum(dxdy, axis=0)
    # insert the initial position at the head of the array
    xy = np.vstack((xy_0, xy))
    # since javascript has no 2D array, it is better to
    # return the x-position and y-position, separately
    return xy[:,0], xy[:,1]