Using a custom time format in Plotly Express timeline

Question

I am using plotly express to make a custom timeline graph object and I want to edit the x(time) axis to display a different time format, but it will only allow for 'datetime'. Is there any way to use a custom time type in plotly using the timeline object? Is there a better framework for this, such as matplotlib or something else?

Answer 1

It is possible to customize time format with plotly, see plotly documentation. Examples shown there use px.line(), but formatting works with px.timeline() the same way.

Example:

presidents = pd.DataFrame([{"name": "Clinton", "start": '1993-01-20', 'end': '2001-01-20'},
                           {"name": "Bush", "start": '2001-01-20', 'end': '2009-01-20'},
                           {"name": "Obama", "start": '2009-01-20', 'end': '2017-01-20'},
                           {"name": "Trump", "start": '2017-01-20', 'end': '2021-01-20'}
                          ])

fig = px.timeline(presidents,
                  x_start="start",
                  x_end="end",
                  y="name"
                 )
fig.update_xaxes(
    dtick="M48",   # display x-ticks every 24 months months
    tickformat="Date:%Y-%m-%d"  # date format
) 
fig.show()

This gives: