pandas 或 matplotlib 中分类或二元变量的时间序列图

Question

我有代表分类变量时间序列的数据。我想在相关连续时间序列的传统线图下方显示类别中的转换，以随着时间的推移展示上下文。我想知道最好的方法来做到这一点。我的尝试是在矩形方面。外观有点奇怪，重要的是 x 轴的轴标签不呈现为日期。

import pandas as pd
import matplotlib.pyplot as plt
import matplotlib as mpl
import numpy as np
from pandas.plotting import register_matplotlib_converters
import matplotlib.dates as mdates
register_matplotlib_converters()

t0 = pd.DatetimeIndex(["2017-06-01 00:00","2017-06-17 00:00","2017-07-03 00:00","2017-08-02 00:00","2017-08-09 00:00","2017-09-01 00:00"])
t1 = pd.DatetimeIndex(["2017-06-01 00:00","2017-08-15 00:00","2017-09-01 00:00"])
df0 = pd.DataFrame({"cat":[0,2,1,2,0,1]},index = t0)
df1 =  pd.DataFrame({"op":[0,1,0]},index=t1)

# Create new plot
fig,ax = plt.subplots(1,figsize=(8,3))

data_layout = {
  "cat" : {0: ('bisque','Low'),
           1: ('lightseagreen','Medium'),
           2: ('rebeccapurple','High')},
  "op" : {0: ('darkturquoise','Open'),
           1: ('tomato','Close')}
           }


vars =("cat","op")


dfs = [df0,df1]

all_ticks = []
leg = []

for j,(v,d) in enumerate(zip(vars,dfs)):
    dvals = d[v][:].astype("d")
    normal = mpl.colors.Normalize(vmin=0, vmax=2.)    

    colors = plt.cm.Set1(0.75*normal(dvals.as_matrix()))
    handles = []
    for i in range(d.count()-1):
        s = d[v].index.to_pydatetime()
        level = d[v][i]
        base = d[v].index[i]
        w = s[i+1] - s[i]
        patch=mpl.patches.Rectangle((base,float(j)),width=w,color=data_layout[v][level][0],height=1,fill=True)
        ax.add_patch(patch)

    for lev in data_layout[v]:    
        print data_layout[v][level]
        handles.append(mpl.patches.Patch(color=data_layout[v][lev][0],label=data_layout[v][lev][1]))
    all_ticks.append(j+0.5)

    leg.append( plt.legend(handles=handles,loc = (3-3*j+1)))

plt.axhline(y=1.,linewidth=3,color="gray")
plt.xlim(pd.Timestamp(2017,6,1).to_pydatetime(),pd.Timestamp(2017,9,1).to_pydatetime())
plt.ylim(0,2)
ax.add_artist(leg[0])  # two legends on one axis
ax.format_xdata = mdates.DateFormatter('%Y-%m-%d')   # This fails
plt.yticks(all_ticks,vars)
plt.show()

生成此内容时没有日期并且有紧张的线条：。我该如何解决？有没有更好的办法呢？

Answer 1

这是一种在 x-axis 上显示日期的方法：

在您的代码中，将失败的行替换为以下行：

ax.xaxis.set_major_formatter((mdates.DateFormatter('%Y-%m-%d')))

但我不记得它应该是什么样子了，你能再给我们看一下 end-result 吗？

pandas 或 matplotlib 中分类或二元变量的时间序列图

Time series plot of categorical or binary variables in pandas or matplotlib

pandas

matplotlib

plot

time-series

categorical-data