使用dataframe中的列为海上绘图的背景着色。

Question

问题

如何使用海航的列对数据帧绘图的背景进行阴影或着色

代码段

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)

产生了这个图表：

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期望输出

根据新列'background'和任何调色板或用户定义的颜色中的值，我希望得到如下内容：

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Answer 1

假设背景在时间点上不重叠，ax.axvspan()可以为您工作。

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)

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