[box-basic] letsplot implementation

[github-actions]

[box-basic] letsplot Implementation

Parent Issue: #203
Spec: specs/box-basic.md
Library: letsplot
Feature Branch: plot/box-basic

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Attempt History

Attempts will be documented below as comments.

[github-actions]

Attempt 1/3

Technical Approach

• Imports: import numpy as np, import pandas as pd, from lets_plot import (
• Plot function: ggplot

Status

• PR: feat(letsplot): implement box-basic #458
• File: plots/letsplot/boxplot/box-basic/default.py
• Workflow: 20002659125

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[github-actions]

🧪 Test Results (PR #458)

Python:

📊 Plot Preview (Python 3.13)

letsplot (default) - UPDATE

Before	After

View version history (3 versions)

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🤖 Generated by gen-preview workflow

[claude]

AI Review - Attempt 1/3

Quality Evaluation

Evaluator	Score	Verdict
Claude	88/100	approve

Criteria Checklist

• VQ-001: Axes labeled correctly ("Group", "Value")
• VQ-002: Visual clarity - minimal theme, subtle grid
• VQ-003: Elements clear - boxes, whiskers, outliers all visible
• VQ-004: No overlap - labels and elements well-spaced
• VQ-005: Legend present - N/A (hidden, appropriate for grouped box plot)
• VQ-006: Colorblind safe - uses distinct colors (blue, yellow, red, green) ← Minor concern: red-green combination
• VQ-007: Image size - 4800 × 2700 px (1600×900 with scale=3)
• VQ-008: Title - "Basic Box Plot" centered and clear
• CQ-001: Type hints - N/A (plot script, not function)
• CQ-002: Docstring - N/A (plot script, not function)
• CQ-003: Input validation - N/A (plot script with inline data)
• CQ-004: Clear error messages - N/A
• CQ-005: No magic numbers - uses named variables for colors
• CR-001: Data accurate - correct columns (group, value) used
• CR-002: Spec compliance - all requirements met (4 groups, quartiles, whiskers, outliers)
• CR-003: Edge cases - N/A (inline data generation)

Issues Found

1. VQ-006 MINOR: Color palette includes red (#DC2626) and green (#059669) which could be challenging for red-green colorblind users. However, since the groups are also distinguished by x-axis position and the colors are not adjacent, this is a minor concern.

AI Feedback for Next Attempt

No critical issues found. Implementation is clean and follows the KISS style guide correctly.
Minor suggestion for future: Consider using a fully colorblind-safe palette like viridis or tab10.

Verdict: APPROVED

The implementation correctly creates a basic box plot using lets-plot with:

• Proper box-and-whisker visualization showing Q1, median, Q3
• Whiskers extending to show data range within 1.5×IQR
• Outliers displayed as individual points
• Clean minimal theme
• Correct figure dimensions
• All spec requirements met