feat(letsplot): implement line-filled

[github-actions]

Implementation: line-filled - letsplot

Implements the letsplot version of line-filled.

File: plots/line-filled/implementations/letsplot.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 traffic over 12 months. The chart uses a blue color (#306998) with a semi-transparent fill (alpha ~0.4) below the line. A solid blue line traces the data points, with blue circular markers at each month. The y-axis shows "Website Visitors" ranging from 0 to approximately 70,000, and the x-axis shows "Month" with values 1-12. The title "line-filled · letsplot · pyplots.ai" appears at the top. The plot uses a minimal theme with subtle gray horizontal grid lines on a white background. The data shows variation with a peak around month 4 (~70,000 visitors) and a dip at month 2 (~55,000 visitors).

Quality Score: 92/100

Criteria Checklist

Visual Quality (36/40 pts)

• VQ-01: Text Legibility (10/10) - Title, axis labels, and tick marks are all clearly readable at appropriate sizes
• VQ-02: No Overlap (8/8) - No overlapping text elements
• VQ-03: Element Visibility (8/8) - Line width and point markers are appropriately sized for 12 data points
• VQ-04: Color Accessibility (5/5) - Single color scheme, no colorblind issues
• VQ-05: Layout Balance (5/5) - Good use of canvas space, data fills the plot area well
• VQ-06: Axis Labels (1/2) - "Month" and "Website Visitors" are descriptive but lack units
• VQ-07: Grid & Legend (1/2) - Grid is subtle and appropriate; minor grid disabled which is good; no legend needed for single series

Spec Compliance (25/25 pts)

• SC-01: Plot Type (8/8) - Correct filled line (area) chart
• SC-02: Data Mapping (5/5) - X=continuous (months), Y=numeric (visitors)
• SC-03: Required Features (5/5) - Semi-transparent fill, visible line on top, fill matches line color
• SC-04: Data Range (3/3) - All data visible, y-axis starts from 0 (correct baseline)
• SC-05: Legend Accuracy (2/2) - No legend needed for single series
• SC-06: Title Format (2/2) - Uses correct format: "line-filled · letsplot · pyplots.ai"

Data Quality (18/20 pts)

• DQ-01: Feature Coverage (7/8) - Shows variation in the data with peaks and valleys; could have more dramatic variation to better showcase the fill
• DQ-02: Realistic Context (7/7) - Website traffic is a perfect real-world scenario for this plot type
• DQ-03: Appropriate Scale (4/5) - Values are realistic for website traffic (50k-70k monthly visitors)

Code Quality (10/10 pts)

• CQ-01: KISS Structure (3/3) - Simple imports → data → plot → save structure, no functions/classes
• CQ-02: Reproducibility (3/3) - Uses np.random.seed(42)
• CQ-03: Clean Imports (2/2) - Only numpy, pandas, lets_plot used
• CQ-04: No Deprecated API (1/1) - Uses current lets-plot API
• CQ-05: Output Correct (1/1) - Saves as plot.png and plot.html

Library Features (3/5 pts)

• LF-01: Uses distinctive library features (3/5) - Uses geom_area, geom_line, geom_point, theme_minimal correctly but doesn't showcase lets-plot specific features like tooltips or interactivity in the plot design

Strengths

• Excellent use of geom_area + geom_line + geom_point combination for a complete filled line visualization
• Perfect title format and well-chosen realistic data context (website traffic)
• Clean code structure following KISS principles with proper reproducibility seed
• Good visual balance with appropriate fill transparency (0.4) and line visibility

Weaknesses

• Axis labels lack units (e.g., "Month (2024)" or "Visitors (thousands)")
• Data variation could be more pronounced to better showcase the filled area effect

Verdict: APPROVED