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empty splom in case of two dimensions

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
42/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
numpy, pandas, python

Research direction

Start with the go.Splom reproduction in the issue, especially the two dimensions, hidden diagonal, and lower-half-only settings. Run the script with fig.show() or fig.write_html() and trace the generated figure behavior. Done means the two-dimensional lower-half-only splom renders its single scatter plot instead of an empty figure.

Written by the indexing model from the issue text.

Description

bug P3

Creating a splom with two dimensions, no diagonal and only the upper or lower half results in an empty figure.

Code that reproduces the issue:

import numpy as np
import pandas as pd
import plotly.graph_objects as go

data = pd.DataFrame({"col1": np.random.rand(10), "col2": np.random.rand(10)})

fig = go.Figure(
    go.Splom(
        dimensions=[{"label": label, "values": data[label]} for label in data.columns],
        diagonal={"visible": False},
        showupperhalf=False,
        showlowerhalf=True,
    ),
)


fig.write_html("test.html")  # or fig.show()
# Gives me an empty plot. Setting `diagonal` or `showupperhalf` to `True` does give a plot

Expected result
A single scatter plot.

Dominant language
Python
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Avg merge
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Merged PRs (30d)
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