1d_rw.py

#for plotting in Jupyter
%pylab inline
#import needed library
from itertools import cycle
from mpl_toolkits.mplot3d import Axes3D
colors = cycle(‘bgrcmykbgrcmykbgrcmykbgrcmyk’)
# Define parameters for the walk
dims = 1
step_n = 10000
step_set = [-1, 0, 1]
origin = np.zeros((1,dims))
# Simulate steps in 1D
step_shape = (step_n,dims)
steps = np.random.choice(a=step_set, size=step_shape)
path = np.concatenate([origin, steps]).cumsum(0)
start = path[:1]
stop = path[-1:]
# Plot the path
fig = plt.figure(figsize=(8,4),dpi=200)
ax = fig.add_subplot(111)
ax.scatter(np.arange(step_n+1), path, c=’blue’,alpha=0.25,s=0.05);
ax.plot(path,c=’blue’,alpha=0.5,lw=0.5,ls=’ — ‘,);
ax.plot(0, start, c=’red’, marker=’+’)
ax.plot(step_n, stop, c=’black’, marker=’o’)
plt.title(‘1D Random Walk’)
plt.tight_layout(pad=0)
plt.savefig(‘plots/random_walk_1d.png’,dpi=250);