Plotly Express labels dict not applying to traces generated with the color keyword

I have a dataframe that I am using to generate an area chart with three components. These components are split out using the color keyword. Unfortunately, the labels keyword only renames the title of columns, not the names of traces generated by the color keyword. In the example below, it would be great to be able to replace steady, new_users and churn with more descriptive labels.

Of course, I can work around this by modifying the original data frame, but the labels dict is so elegant…

[nicolaskruchten]

Right, the labels only operate on column names today, although I can see why for figures like this one, legend item text like “steady” could be thought of as a “label”. I might be open to a new keyword argument for this to remap values…

in the meantime, you can swap these out post-px like this:

import plotly.express as px

df = px.data.tips()

fig = px.scatter(df, x="total_bill", y="tip", color="day")
value_map = { "Sun": "Sunday",  "Sat": "Saturday" }
for trace in fig.data:
    trace.name = value_map.get(trace.name, trace.name)

# or the chainable function version
fig.for_each_trace(lambda t: t.update(name=value_map.get(t.name, t.name)))

fig.show()

[janosh]

While these strings come from column data, when shown in the legend, they should count as labels and be subject to px.defaults.labels imo.