[scatter-color-groups] letsplot implementation

[github-actions]

[scatter-color-groups] letsplot Implementation

Parent Issue: #208
Spec: specs/scatter-color-groups.md
Library: letsplot
Feature Branch: plot/scatter-color-groups

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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
• Config: color=species

Status

• PR: feat(letsplot): implement scatter-color-groups #372
• File: plots/letsplot/point/scatter-color-groups/default.py
• Workflow: 19995640812

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[github-actions]

🧪 Test Results (PR #372)

Python:

📊 Plot Preview (Python 3.13)

letsplot (default) - NEW

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🤖 Generated by gen-preview workflow

[claude]

AI Review - Attempt 1/3

Quality Evaluation

Evaluator	Score	Verdict
Claude	92/100	approve

Criteria Checklist

• VQ-001: Axes labeled correctly ("Sepal Length (cm)", "Sepal Width (cm)")
• VQ-002: Grid is subtle (minimal theme with light gridlines)
• VQ-003: Elements clear (size=4, alpha=0.7, distinct colors)
• VQ-004: No overlap (legend positioned cleanly on right)
• VQ-005: Legend present (shows Species with 3 categories)
• VQ-006: Colorblind safe (blue #306998, yellow #FFD43B, green #059669 - no red-green)
• VQ-007: Image size correct (1600x900 with scale=3 = 4800x2700)
• VQ-008: Title present and centered ("Iris Sepal Dimensions by Species")
• [N/A] CQ-001: Type hints (KISS style for plots)
• [N/A] CQ-002: Docstring (KISS style for plots)
• [N/A] CQ-003: Input validation (KISS style for plots)
• [N/A] CQ-004: Clear error messages (KISS style for plots)
• CQ-005: No magic numbers (colors defined as variable, size/alpha explicit)
• CR-001: Data accurate (iris-like data with sepal_length, sepal_width, species)
• CR-002: Spec compliance (scatter plot with color groups, all requirements met)
• CR-003: Edge cases (N/A for KISS-style static data script)

Score Breakdown

Base: 50 points
+10 VQ-001 (axes labeled)
+5  VQ-002 (visual clarity)
+8  VQ-003 (elements clear)
+9  VQ-004 (no overlap)
+7  VQ-005 (legend present)
+6  VQ-006 (colorblind safe)
+4  VQ-007 (image size)
+3  VQ-008 (title)
+10 CR-001 (data accurate)
+10 CR-002 (spec compliance)
-10 (N/A criteria not counted)
= 92/100

Issues Found

None - implementation meets all applicable quality criteria.

Strengths

1. Clean implementation following letsplot grammar of graphics
2. Proper use of scale_color_manual with colorblind-safe palette
3. Correct figure sizing (1600x900 base × 3 scale = 4800×2700 target)
4. Appropriate font sizes for title, axes, and legend
5. Data clearly shows three distinct "color clouds" per spec requirement

AI Feedback for Next Attempt

No changes needed - implementation is excellent.

Verdict: APPROVED ✅