feat(pygal): implement line-basic

[github-actions]

Implementation: line-basic - pygal

Implements the pygal version of line-basic.

File: plots/line-basic/implementations/pygal.py

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

The plot displays a clean line chart showing monthly average temperatures for a temperate climate. A single soft blue line (#306998) connects 12 data points across the months (Jan-Dec), forming the characteristic bell curve of seasonal temperature variation. Small circular markers are visible at each data point. The title "line-basic · pygal · pyplots.ai" is centered at the top in gray text. The Y-axis is labeled "Temperature (°C)" with values ranging from ~2 to 22, and the X-axis is labeled "Month" with all 12 month abbreviations clearly displayed. Subtle horizontal dotted grid lines aid readability. A legend reading "Average Temperature" appears at the bottom left. The overall design is clean with a white background.

Quality Score: 92/100

Criteria Checklist

Visual Quality (36/40 pts)

• VQ-01: Text Legibility (9/10) - Title and axis labels are clearly readable; tick labels slightly smaller than ideal
• VQ-02: No Overlap (8/8) - No overlapping text elements
• VQ-03: Element Visibility (7/8) - Dots visible but could be slightly larger; line width appropriate
• VQ-04: Color Accessibility (5/5) - Single blue color, excellent contrast on white background
• VQ-05: Layout Balance (5/5) - Well-proportioned with good use of space
• VQ-06: Axis Labels (2/2) - Descriptive labels with units: "Temperature (°C)", "Month"
• VQ-07: Grid & Legend (0/2) - Grid is subtle (good), but legend placement at bottom-left is awkward and small

Spec Compliance (25/25 pts)

• SC-01: Plot Type (8/8) - Correct line chart implementation
• SC-02: Data Mapping (5/5) - X=months (sequential), Y=temperature (continuous) correctly mapped
• SC-03: Required Features (5/5) - Line connecting points, markers on data points, grid lines present
• SC-04: Data Range (3/3) - All 12 months visible, Y-axis range appropriate
• SC-05: Legend Accuracy (2/2) - Legend correctly labeled "Average Temperature"
• SC-06: Title Format (2/2) - Uses correct format: "line-basic · pygal · pyplots.ai"

Data Quality (19/20 pts)

• DQ-01: Feature Coverage (7/8) - Shows clear seasonal trend with peak in summer; could show more variation
• DQ-02: Realistic Context (7/7) - Monthly temperature data is a classic, real-world use case
• DQ-03: Appropriate Scale (5/5) - Temperature values (2.3°C to 22.1°C) realistic for temperate climate

Code Quality (9/10 pts)

• CQ-01: KISS Structure (3/3) - Clean imports → data → plot → save structure, no functions/classes
• CQ-02: Reproducibility (3/3) - Deterministic data (no random generation)
• CQ-03: Clean Imports (2/2) - Only pygal and Style imported, both used
• CQ-04: No Deprecated API (1/1) - Current pygal API used
• CQ-05: Output Correct (0/1) - Saves both plot.png and plot.html (correct)

Library Features (3/5 pts)

• LF-01: Uses distinctive library features (3/5) - Uses custom Style class and pygal-specific options (show_dots, dots_size, stroke_style), but doesn't leverage tooltips or other interactive SVG features that make pygal distinctive

Strengths

• Clean, minimal design that matches spec requirements perfectly
• Excellent use of custom Style for font sizing on large canvas
• Realistic temperature data that clearly demonstrates seasonal trends
• Proper title format following pyplots.ai conventions
• Good color choice with accessible contrast

Weaknesses

• Legend at bottom-left appears small and somewhat disconnected from the chart
• Font sizes in the library rules suggest smaller values (28/18/16) but implementation uses larger (72/48/42) - while this works for the large canvas, it deviates from the template

Verdict: APPROVED