wrong location of xticks in plotly express
Open
Nobody has claimed this yet.
bug
P3
- Dominant language
- Python
- Stars
- 18.8k
- Forks
- 2.8k
- Avg merge
- 16h 26m
- Merged PRs (30d)
- 21
Description
plotly version: 5.9.0
Python: 3.9.13 on Apple silicon running OSX 12.2
Reproducible example:
import pandas as pd
import plotly.express as px
df = pd.DataFrame({
'date': pd.date_range(start='2022-01-01', end='2022-06-30', freq='1D'),
'y': 1,
})
df['weekday'] = df['date'].dt.weekday.astype('str')
df = df.set_index('date')
df = df.groupby('weekday').resample('M').agg({'y': 'sum'}).reset_index()
px.bar(df, x=df['date'], y=df['y'], color=df['weekday'])
This leads to:

One can see that the last bar is shown above July whereas it actually corresponds to June. All xticks should be moved one month back on this graph.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by running the provided Python example through the plotly.express px.bar entry point and inspect how the resampled date values are used for x-axis ticks. The fix is complete when the final bar is labeled under June rather than July and the other month labels remain correctly aligned.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- pandas, python
- Domain
- data-visualization
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100