要根据分类变量'z'用不同颜色绘制散点图，可以使用字典将'z'的每个唯一值Map到特定颜色，然后将Map的颜色作为'c'参数传递：

df = pd.DataFrame({
    "x": [1, 2, 3],
    "y": [4, 5, 6],
    "z": ["A", "B", "C"],
})

color_map = {"A": "red", "B": "green", "C": "blue"}

df.plot(
    x="x",
    y="y",
    kind="scatter",
    c=df['z'].map(color_map),
    colormap='viridis',
)

plt.show()

你可以简单地在'z'中添加一些颜色

import pandas as pd

df = pd.DataFrame({
    "x": [1,2 ,3],
    "y": [4, 5, 6],
    "z": ["red", "blue", "green"],
})

df.plot(
    x="x",
    y="y",
    kind="scatter",
    c="z",
)