python - 使用数据框中的列为 seaborn 图的背景着色

Question

题
如何为 seaborn 的背景着色或着色使用 dataframe 的列绘图?
代码片段

import numpy as np
import seaborn as sns; sns.set()
import matplotlib.pyplot as plt
fmri = sns.load_dataset("fmri")
fmri.sort_values('timepoint',inplace=True)
ax = sns.lineplot(x="timepoint", y="signal", data=fmri)
arr = np.ones(len(fmri))
arr[:300] = 0
arr[600:] = 2
fmri['background'] = arr

ax = sns.lineplot(x="timepoint", y="signal", hue="event", data=fmri)

产生了这张图:

期望输出
根据新列 'background' 中的值，我想要什么和任何 palette或用户定义 colors ，像这样:

Answer 1

ax.axvspan()可以为您工作，假设背景在时间点上不重叠。

import numpy as np
import seaborn as sns; sns.set()
import matplotlib.pyplot as plt
fmri = sns.load_dataset("fmri")
fmri.sort_values('timepoint',inplace=True)
arr = np.ones(len(fmri))
arr[:300] = 0
arr[600:] = 2
fmri['background'] = arr
fmri['background'] = fmri['background'].astype(int).astype(str).map(lambda x: 'C'+x)

ax = sns.lineplot(x="timepoint", y="signal", hue="event", data=fmri)
ranges = fmri.groupby('background')['timepoint'].agg(['min', 'max'])
for i, row in ranges.iterrows():
    ax.axvspan(xmin=row['min'], xmax=row['max'], facecolor=i, alpha=0.3)