ストリームグラフで構成比のうねりを見る

import numpy as np
import matplotlib.pyplot as plt

x = np.arange(0, 24)
rng = np.random.default_rng(24)
segments = []
for phase in range(4):
    trend = 12 + 6 * np.sin(2 * np.pi * (x + phase * 3) / 12)
    noise = rng.normal(0, 1.2, size=x.size)
    segments.append(np.clip(trend + noise, 0, None))
stacked = np.vstack(segments)

fig, ax = plt.subplots(figsize=(6.4, 4))
colors = ["#0ea5e9", "#22d3ee", "#818cf8", "#f472b6"]
ax.stackplot(x, stacked, baseline="wiggle", colors=colors, alpha=0.9)
ax.set_xticks(range(0, 24, 3), labels=[f"{h}時" for h in range(0, 24, 3)])
ax.set_title("チャネル別流入構成のストリームグラフ")
ax.set_ylabel("セッション数")
ax.set_xlabel("時間帯")
ax.spines[["right", "top"]].set_visible(False)
ax.grid(axis="x", alpha=0.15)

legend_labels = ["自然検索", "広告", "SNS", "紹介"]
ax.legend(legend_labels, loc="upper left", frameon=False)

fig.tight_layout()
fig.savefig("static/images/visualize/advanced/streamgraph.svg")