feat(pygal): implement line-interactive

[github-actions]

Implementation: line-interactive - pygal

Implements the pygal version of line-interactive.

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

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

The plot displays a line chart showing daily temperature data for 2024. The chart uses a blue color (#306998 - Python Blue) for the line with small dots marking each data point. The y-axis shows "Temperature (°C)" ranging from approximately -2 to 36 degrees. The x-axis shows "Date" with major labels approximately every 30 days (Jan 01, Jan 31, Mar 01, Mar 31, etc.) rotated at 45 degrees. The title reads "Daily Temperature 2024 · line-interactive · pygal · pyplots.ai" at the top. A legend labeled "Temperature" appears at the bottom. The data shows a clear seasonal sinusoidal pattern with winter lows around 0-8°C and summer highs around 25-36°C, with daily noise variation creating the jagged appearance. The background is white with subtle horizontal grid lines.

Quality Score: 91/100

Criteria Checklist

Visual Quality (37/40 pts)

• VQ-01: Text Legibility (9/10) - Title and axis labels are clear and readable; tick labels adequately sized for 4800x2700 canvas
• VQ-02: No Overlap (8/8) - No overlapping text; x-axis labels well-spaced with major labels every 30 days
• VQ-03: Element Visibility (7/8) - Line clearly visible; dots appropriately sized for 365 data points; line could be slightly thicker for better visibility
• VQ-04: Color Accessibility (5/5) - Single series in blue is colorblind-safe; good contrast against white background
• VQ-05: Layout Balance (4/5) - Good proportions; plot fills reasonable canvas area; slight margin imbalance at bottom with legend
• VQ-06: Axis Labels (2/2) - Descriptive labels with units: "Temperature (°C)" and "Date"
• VQ-07: Grid & Legend (2/2) - Subtle horizontal grid lines; legend well-positioned at bottom

Spec Compliance (23/25 pts)

• SC-01: Plot Type (8/8) - Correct interactive line chart
• SC-02: Data Mapping (5/5) - Date on X-axis, temperature on Y-axis correctly assigned
• SC-03: Required Features (3/5) - Hover tooltips present in HTML output; however PNG is static - zoom/pan/range selection only work in HTML version
• SC-04: Data Range (3/3) - Full year of data shown with appropriate axis range
• SC-05: Legend Accuracy (2/2) - Legend correctly labels the temperature series
• SC-06: Title Format (2/2) - Uses correct format: "Daily Temperature 2024 · line-interactive · pygal · pyplots.ai"

Data Quality (19/20 pts)

• DQ-01: Feature Coverage (7/8) - Shows seasonal variation with daily noise; demonstrates large time series handling; could show multiple series for richer comparison
• DQ-02: Realistic Context (7/7) - Weather station temperature data is a neutral, real-world scenario perfect for time series
• DQ-03: Appropriate Scale (5/5) - Temperature values are realistic (-2°C to 36°C annual range is plausible 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) - Uses np.random.seed(42) for consistent output
• CQ-03: Clean Imports (2/2) - All imports are used (numpy, pandas, pygal, Style)
• CQ-04: No Deprecated API (1/1) - Uses current pygal API
• CQ-05: Output Correct (0/1) - Saves as plot.png AND plot.html (both are acceptable for pygal)

Library Features (3/5 pts)

• LF-01: Uses distinctive library features (3/5) - Good use of pygal's Style customization, custom tooltips with formatted labels, and dual SVG/PNG/HTML output; could leverage more pygal-specific features like built-in animations or explicit interactivity configurations

Strengths

• Clean seasonal temperature pattern with realistic daily variation demonstrates time series well
• Excellent custom Style configuration with appropriate font sizes for large canvas
• Proper tooltip customization with formatted date and temperature values
• Good axis labeling with units (°C) and descriptive titles
• Smart x-axis label management showing only major labels every 30 days to prevent clutter
• Outputs both PNG and HTML for static/interactive versions

Weaknesses

• PNG output is inherently static; the interactive features (hover, zoom, pan, range selection) specified in the spec are only available in the HTML output - this is a limitation of the PNG format, not a code issue
• Single data series limits feature demonstration; could show multiple locations or metrics for comparison

Verdict: APPROVED