feat(plotnine): implement line-filled

[github-actions]

Implementation: line-filled - plotnine

Implements the plotnine version of line-filled.

File: plots/line-filled/implementations/plotnine.py

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

The plot displays a filled line chart showing monthly website visitors over a 12-month period. The area beneath the line is filled with a muted blue color (#306998) at approximately 40% transparency, creating a clear area chart effect. A darker blue line of the same color traces the top edge of the filled region. The y-axis labeled "Website Visitors" ranges from 0 to approximately 70,000, and the x-axis labeled "Month" shows values from about 1 to 12.5 (displayed as decimal values like 2.5, 5.0, 7.5, etc.). The title "line-filled · plotnine · pyplots.ai" is prominently displayed at the top. The data shows some variation with peaks around months 4 and 11, and troughs around months 2 and 8. The background is clean with a subtle grid, and the overall layout is well-balanced with the plot filling the canvas appropriately.

Quality Score: 91/100

Criteria Checklist

Visual Quality (36/40 pts)

• VQ-01: Text Legibility (10/10) - Title, axis labels, and tick labels are all clearly readable at the target resolution
• VQ-02: No Overlap (8/8) - No overlapping text elements
• VQ-03: Element Visibility (8/8) - Line is clearly visible (size=2), fill alpha (0.4) provides good contrast
• VQ-04: Color Accessibility (5/5) - Single color scheme, no colorblind concerns
• VQ-05: Layout Balance (5/5) - Plot fills canvas well with balanced margins
• VQ-06: Axis Labels (1/2) - Labels are descriptive but lack units (could be "Website Visitors (thousands)")
• VQ-07: Grid & Legend (1/2) - Grid is subtle but x-axis shows decimal months (2.5, 5.0) instead of integers which is slightly confusing

Spec Compliance (25/25 pts)

• SC-01: Plot Type (8/8) - Correct filled line/area chart type
• SC-02: Data Mapping (5/5) - X (Month) and Y (Visitors) correctly assigned
• SC-03: Required Features (5/5) - Semi-transparent fill (alpha=0.4), visible line on top, fill matches line color, baseline at y=0
• SC-04: Data Range (3/3) - All data visible, y-axis starts at 0
• SC-05: Legend Accuracy (2/2) - No legend needed for single series
• SC-06: Title Format (2/2) - Correct format: "line-filled · plotnine · pyplots.ai"

Data Quality (18/20 pts)

• DQ-01: Feature Coverage (8/8) - Shows variation over time with peaks and troughs, demonstrates the filled area effect well
• DQ-02: Realistic Context (7/7) - Website traffic is a neutral, realistic business scenario
• DQ-03: Appropriate Scale (3/5) - Values (50k-70k visitors) are plausible, but months shown as decimals (2.5, 5.0) is odd for discrete monthly data

Code Quality (9/10 pts)

• CQ-01: KISS Structure (3/3) - Simple imports → data → plot → save structure
• CQ-02: Reproducibility (3/3) - np.random.seed(42) is set
• CQ-03: Clean Imports (2/2) - All imports are used
• CQ-04: No Deprecated API (1/1) - Using current plotnine API
• CQ-05: Output Correct (0/1) - Saves as plot.png but uses verbose=False instead of standard approach

Library Features (3/5 pts)

• LF-01: Uses distinctive library features (3/5) - Uses ggplot grammar correctly with geom_area + geom_line layering, theme_minimal, and element_text customization. Good use of grammar of graphics but could leverage more plotnine-specific features.

Strengths

• Excellent layering of geom_area and geom_line to create the filled effect with visible line on top
• Well-chosen alpha value (0.4) matches spec recommendation (0.3-0.5)
• Clean, professional appearance with consistent Python blue color (#306998)
• Good use of theme customization for text sizing and grid styling
• Realistic website traffic scenario with appropriate seasonal variation

Weaknesses

• X-axis displays months as decimals (2.5, 5.0, 7.5) instead of integers (1, 2, 3...12) which is confusing for monthly data
• Y-axis label could include units (e.g., "Website Visitors (thousands)" or use K formatting)

Verdict: APPROVED