from io import StringIO

import jupyterlab as jpl
import matplotlib as mpl
import matplotlib.pyplot as plt
import numpy as np
import pandas as pd

csv_file = StringIO("""\
x,y1,y2
0,8,18
1,18,11
2,24,8
3,18,11
4,8,18
5,18,26
6,24,42
7,18,
8,8,
9,18,
""")

df = pd.read_csv(csv_file)


fig, axes = plt.subplots(2, 2, sharex="all", sharey="all", figsize=(12, 6))
fig.patch.set_facecolor("#ffffff")  

for row_idx, row in enumerate(axes):
    for col_idx, axis in enumerate(row):
        for y in ["y1", "y2"]:
            axis.plot(
                df["x"],
                df[y],
                label=r"$ " + y + r" $",
            )
            
        if row_idx == 0:
            axis.fill_between(
                df["x"],
                df["y1"],
                df["y2"],
                where=df["y1"] <= df["y2"],
                facecolor="#94C154",
                interpolate=True,
            )
            axis.set_title((axis.get_title() + " & " if axis.get_title() else "") + "'where <='")
        if col_idx == 0:
            axis.fill_between(
                df["x"],
                df["y1"],
                df["y2"],
                where=df["y1"] >= df["y2"],
                facecolor="#DD4814",
                interpolate=True,
            )
            axis.set_title((axis.get_title() + " & " if axis.get_title() else "") + "'where >='")
        if row_idx == 1 and col_idx == 1:
            axis.fill_between(
                df["x"],
                df["y1"],
                df["y2"],
                facecolor="#F6A800",
                interpolate=True,
            )
            axis.set_title("without 'where'")

        if any(axis.get_legend_handles_labels()):
            axis.legend()

fig.suptitle(
    "matplotlib: v" + mpl.__version__ + " (" + mpl.get_backend() + ")" + "\n"
    + "jupyterlab: v" + jpl.__version__ + "\n"
    + "numpy: v" + np.__version__ + "\n"
    + "pandas: v" + pd.__version__,
    #y=1.15
)

fig.tight_layout()
plt.show(fig)