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Slider in `scatter_3d` and `scatter` makes some data points go missing

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
numpy, pandas, plotly, python

Research direction

Run the provided Python MWE in plot_scatter_3d_mwe and compare the animated 2D and 3D scatter behavior across threshold frames. Trace how animation_frame and animation_group are represented in the generated figure; done means all four categories and their data points remain available at every slider position.

Written by the indexing model from the issue text.

Description

bug P3

Only 2 out of 4 categories are plotted when I use a slider. Other data points do not appear at all. When I slide the slider, different categories are plotted. E.g. in the MWE below, only TP and FP show up when the slider is below 0.9. At 0.9 only TN and FN show up.

This behavior also happens for both 2d and 3d scatter plots. See the MWE below for 3d.

image

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

def plot_scatter_3d_mwe():
    # Create a small DataFrame with fake data
    data = {
        'Dim1': np.random.rand(10),
        'Dim2': np.random.rand(10),
        'Dim3': np.random.rand(10),
        'due': [1, 0, 1, 0, 1, 0, 1, 0, 1, 0],
        'serial_number': range(10),
        'predicted_probabilities': [0.9, 0.8, 0.4, 0.2, 0.6, 0.7, 0.1, 0.5, 0.3, 0.95]
    }

    df = pd.DataFrame(data)
    thresholds = np.arange(0, 1.1, 0.1)
    all_frames = []

    for threshold in thresholds:
        # Recalculate predictions based on the threshold
        predicted = (df['predicted_probabilities'] >= threshold).astype(int)
        
        # Create the 4 categories for coloring: TP, TN, FP, FN
        conditions = [
            (df['due'] == 1) & (predicted == 1),  # TP
            (df['due'] == 0) & (predicted == 0),  # TN
            (df['due'] == 0) & (predicted == 1),  # FP
            (df['due'] == 1) & (predicted == 0),  # FN
        ]
        categories = ['TP', 'TN', 'FP', 'FN']
        
        # Assign the categories to a new column
        df['category'] = np.select(conditions, categories, default='Unknown')
        df['threshold'] = threshold  # Add threshold as a column for animation frame
        
        all_frames.append(df.copy())

    # Concatenate all frames for animation
    df_all_frames = pd.concat(all_frames)

    # Plot the scatter 3D with the categories as color and animate over thresholds
    fig = px.scatter_3d(df_all_frames,
                        x='Dim1', y='Dim2', z='Dim3',
                        color='category',
                        animation_frame='threshold',
                        animation_group='serial_number')

    fig.show()

# Call the function
plot_scatter_3d_mwe()
Dominant language
Python
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