walk.py

# 加载库
import numpy as np
import pandas as pd
from ggplot import *

# 生成二维随机游走数据
def walk(n):
    NS = randint(0,2,size=n)
    WE = 1 - NS
    xstep = np.random.choice([1,-1],size=n,replace=True) * WE
    ystep = np.random.choice([1,-1],size=n,replace=True) * NS
    x = cumsum(xstep)
    y = cumsum(ystep)
    return array([x,y])
res = walk(2**12)
# 将结果转为dataframe
data = pd.DataFrame({'x':res[0],'y':res[1]})
# 结果绘图
ggplot(aes(x='x', y='y'), data=data) + geom_line()