plotly / plotly/plotly.py

px.ecdf // x_log leads to shifted marginal histogram

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bug P3
Dominant language
Python
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Description

When trying to display a marginal histogram combined with log_x = true, the histogram does not seem to get placed correclty.

Minimal reproducible example (plotly 5.4.0):

import plotly.express as px
import pandas as pd
import numpy as np

df = pd.DataFrame({'data': np.random.randn(10000)+8})
fig = px.ecdf(df, x='data', marginal='histogram', log_x=True)
fig.show()

I expect the histogram's median at 8 (normal distribution with offset of 8), but it is placed somewhere at more than 11. The actual ecdf is displayed correctly. With log_x = False, both the histogram and the ecdf are displayed correctly.

Contributor guide

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First steps

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Research direction

Start by running the minimal px.ecdf example from the issue and inspect the marginal histogram handling when log_x=True. Trace the ECDF and histogram placement paths, then add a regression test showing that the histogram median aligns with the source data while the ECDF remains correct.

Written by the indexing model from the issue text.

Assessment

Tech stack
numpy, 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

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