Visual index of common Brazilian woods

import polars as pl
import altair as alt

df = pl.read_csv("data.csv")

(
    alt.Chart(df)
    .mark_image(width=100, height=100)
    .encode(
        x=alt.X("janka_hardness_lbf:Q", title="Janka hardness (lbf)"),
        y=alt.Y(
            "pixel_darkness_pct:Q",
            title="Pixel darkness (%)",
            scale=alt.Scale(domain=[0, 100]),
        ),
        url="image_url:N",
        tooltip=[
            alt.Tooltip("english_name:N", title="English name"),
            alt.Tooltip("portuguese_name:N", title="Portuguese name"),
            alt.Tooltip("scientific_name:N", title="Scientific name"),
            alt.Tooltip("janka_hardness_lbf:Q", title="Janka hardness (lbf)"),
            alt.Tooltip("pixel_darkness_pct:Q", title="Pixel darkness (%)"),
        ],
    )
    .properties(
        title=alt.TitleParams(
            text="Visual index of common Brazilian woods",
            subtitle=[
                "Janka hardness (lbf): force to embed a steel ball halfway into wood.",
                "Pixel darkness (%): average blackness of monochrome pixels.",
            ],
        ),
        width="container",
        height=600,
    )
)