我已经经历过this https://community.plotly.com/t/custom-si-unit-prefixes/29739, this https://stackoverflow.com/questions/40774677/d3-formatting-tick-value-to-show-b-billion-instead-of-g-giga以及其他一些类似的帖子。他们都用 javascript 提供了解决方案，但我无法将其移植到 python 中。如有帮助，将不胜感激。

当我将值传递给customdata它足够大到十亿，它显示符号为 G（代表千兆）而不是 B，而plotly 默认为 B，可以在图像中看到比较。有没有办法用B代替G？

import pandas as pd
import plotly.express as px

df = pd.DataFrame({'x':[500,3000,50000,100000,7000000,80000000,400000000,9000000000]})
more_data = [100,3000,50000,600000,2000000,90000000,500000000,3000000000]

fig = px.line(df, log_y=True)
fig.update_traces(mode='lines+markers',
                  customdata=more_data,
                  hovertemplate='%{y}<br>%{customdata:,.1s}')

这不会是有史以来最优雅的解决方案，但它可以解决您的问题。如果你仔细观察你的图，你在索引 1 上也有问题，其中数据过多3000<br>3k.

所以我实际上是在明确地编写悬停数据。我们需要这个函数human_format from here https://stackoverflow.com/a/45846841/4819376.

Data

import pandas as pd
import plotly.express as px
df = pd.DataFrame({'x': [500,3000,50000,100000,7000000,80000000,400_000_000,9_000_000_000],
                  'more_data': [100,3000,50000,600000,2000000,90000000,500000000,3_000_000_000]})

写入悬停数据

def human_format(num):
    num = float('{:.3g}'.format(num))
    magnitude = 0
    while abs(num) >= 1000:
        magnitude += 1
        num /= 1000.0
    return '{}{}'.format('{:f}'.format(num).rstrip('0').rstrip('.'), 
                         ['', 'K', 'M', 'B', 'T'][magnitude])

df["hover_data"] = df.apply(lambda r: 
    f"{human_format(r['x'])}<br>{human_format(r['more_data'])}",
                            axis=1)

Plot

fig = px.line(df, 
              y="x", log_y=True)
fig.update_traces(mode='lines+markers',
                  customdata=df['hover_data'],
                  hovertemplate='%{customdata}')