Нильс дал вам правильный ответ для проверки документации matplotlib
Пустые данные
import pandas as pd
import numpy as np
from matplotlib import pyplot as plt
series1 = pd.Series(np.random.rand(20))
series2 = pd.Series(np.random.rand(20)+0.3)
График
plt.fill_between(series1.index, series1, series2, where=series2>=series1, facecolor='green', alpha=0.5, interpolate=True)
plt.fill_between(series1.index, series2, series1, where=series2<=series1, facecolor='red', alpha=0.5, interpolate=True)
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