feat(letsplot): implement circos-basic

[github-actions]

Implementation: circos-basic - python/letsplot

Implements the python/letsplot version of circos-basic.

File: plots/circos-basic/implementations/python/letsplot.py

Parent Issue: #3005

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

Light render (plot-light.png): The plot displays on a warm off-white (#FAF8F1) surface with a professional circular layout. The title "circos-basic · letsplot · anyplot.ai" is dark, bold, and clearly readable at 26pt. Eight chromosomes (Chr1-Chr8) are arranged around the outer ring with distinct custom colors (blues, yellow, green, red, purple, teal, orange). The chromosome labels are positioned outside the circle, dark, 14pt bold, and fully legible. Two concentric expression tracks radiate inward from the chromosome ring with varying opacity levels (0.65 and 0.8 alpha). Ten semi-transparent ribbon connections (alpha=0.45) bridge between chromosomes, with width proportional to connection strength. A bottom-positioned legend clearly maps all eight chromosomes to their colors. All text elements are readable with proper contrast against the light background, and all data elements (rings, tracks, ribbons) are clearly distinguishable and visible.

Dark render (plot-dark.png): The same circular structure displays on a warm near-black (#1A1A17) surface. The title is now light cream (#F0EFE8) and maintains full readability against the dark background. Chromosome labels are light-colored and clearly visible outside the circle. Critically, all eight chromosome colors are identical to the light render, confirming that only chrome (background, text, legend) has flipped between themes—the data colors remain constant. The concentric tracks and ribbon connections maintain their structure and proportions. The legend is visible with light text. No dark-on-dark failures are present; the INK token (#F0EFE8) provides strong contrast against PAGE_BG (#1A1A17), and all data elements are visible and properly distinguished. Both renders demonstrate flawless theme adaptation.

Score: 91/100

Category	Score	Max
Visual Quality	30	30
Design Excellence	14	20
Spec Compliance	15	15
Data Quality	15	15
Code Quality	10	10
Library Mastery	7	10
Total	91	100

Visual Quality (30/30)

• VQ-01: Text Legibility (8/8) - Title 26pt bold, chromosome labels 14pt bold, all readable in both renders with proper contrast
• VQ-02: No Overlap (6/6) - Chromosome labels positioned outside circle, no text collisions, ribbon layering is clean
• VQ-03: Element Visibility (6/6) - All ribbons, tracks, and rings visible with appropriate transparency for data density
• VQ-04: Color Accessibility (2/2) - Custom chromosome colors distinct and colorblind-friendly for genomic domain
• VQ-05: Layout & Canvas (4/4) - Square format 3600×3600px appropriate for circular plot, well-proportioned
• VQ-06: Axis Labels & Title (2/2) - Title "circos-basic · letsplot · anyplot.ai" correct, no axes needed for polar plot
• VQ-07: Palette Compliance (2/2) - Plot backgrounds correct, data colors identical between renders, theme-adaptive chrome only

Design Excellence (14/20)

• DE-01: Aesthetic Sophistication (6/8) - Custom chromosome palette with intentional color choices, carefully calibrated alpha values (0.45, 0.65, 0.8, 0.95)
• DE-02: Visual Refinement (4/6) - Hidden axes, clean circular arrangement with gaps, generous whitespace, appropriate legend placement
• DE-03: Data Storytelling (4/6) - Clear visual hierarchy, ribbon width encodes strength, transparency progression emphasizes importance

Spec Compliance (15/15)

• SC-01: Plot Type (5/5) - Authentic circos plot with concentric tracks and ribbon connections
• SC-02: Required Features (4/4) - All present: 8 segments, 10 connections, 2 expression tracks, labels, legend
• SC-03: Data Mapping (3/3) - Segments positioned correctly, ribbon width proportional to values, track heights encode expression
• SC-04: Title & Legend (3/3) - Correct title format, legend shows all chromosomes with matching colors

Data Quality (15/15)

• DQ-01: Feature Coverage (6/6) - Complete circos: outer ring, expression tracks, connections, labels, legend
• DQ-02: Realistic Context (5/5) - Realistic genomic data (chromosomes, expression levels), authentic bioinformatics use case
• DQ-03: Appropriate Scale (4/4) - Chromosome sizes (120-50 Mb), connection values (8-25), expression normalized 0-1

Code Quality (10/10)

• CQ-01: KISS Structure (3/3) - No functions/classes, straightforward data generation and plotting
• CQ-02: Reproducibility (2/2) - Uses np.random.seed(42) for deterministic output
• CQ-03: Clean Imports (2/2) - Focused imports, all used, no extraneous dependencies
• CQ-04: Code Elegance (2/2) - Well-organized, no fake functionality, appropriate complexity
• CQ-05: Output & API (1/1) - Correct plot-{THEME}.png and plot-{THEME}.html output format

Library Mastery (7/10)

• LM-01: Idiomatic Usage (4/5) - Idiomatic letsplot: ggplot grammar, proper geom/scale/coord API
• LM-02: Distinctive Features (3/5) - Uses ggsave() scale parameter, HTML export, coord_fixed() for aspect

Score Caps Applied

• None applied - no penalties triggered

Strengths

• Proper theme-adaptive rendering with correct color tokens (INK, PAGE_BG) in both renders
• All text clearly readable and properly sized with no dark-on-dark or light-on-light failures
• Excellent use of transparency layering (0.45, 0.65, 0.8, 0.95) to show hierarchy without clutter
• Complete circular geometry with precise angular calculations and proportional ribbons
• All specification requirements met (8 segments, 10 connections, 2 expression tracks, labels, legend)
• Reproducible data generation with realistic genomic data (chromosome sizes, expression values)
• Clean, idiomatic letsplot code using ggplot grammar with high-resolution PNG scaling
• Legend clearly shows all chromosomes with appropriate bottom positioning

Weaknesses

• (None identified - this is a well-executed implementation)

AI Feedback for Next Attempt

No revisions needed. This implementation meets all specification requirements and quality standards. The theme adaptation is flawless, code is clean and idiomatic, and the circular layout effectively communicates genomic relationships through ribbon connections and expression tracks.

Verdict: APPROVED