feat(highcharts): implement area-stacked-confidence

[github-actions]

Implementation: area-stacked-confidence - highcharts

Implements the highcharts version of area-stacked-confidence.

File: plots/area-stacked-confidence/implementations/highcharts.py

Parent Issue: #3549

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

The plot displays a stacked area chart showing renewable energy consumption by source (Solar, Wind, Hydro) over 8 quarters from Q1 2023 to Q4 2024. The three main series are stacked with Solar (gold/yellow) at the bottom, Wind (dark blue) in the middle, and Hydro (cyan/teal) at the top. Each series has a visible lighter-shaded confidence band extending above and below the main area. The areas use smooth spline interpolation (areaspline). The Y-axis shows "Energy Consumption (GWh)" ranging from 0 to ~115, and the X-axis shows "Quarter" with categorical labels. The title follows the required format "area-stacked-confidence · highcharts · pyplots.ai" with a subtitle explaining the data. A legend is positioned in the top-right corner with a white background showing all three series. The color palette uses yellow, blue, and cyan which are colorblind-friendly. Data markers with white borders are visible on each data point.

Quality Score: 91/100

Criteria Checklist

Visual Quality (36/40 pts)

• VQ-01: Text Legibility (10/10) - Title, subtitle, axis labels, and tick labels are all clearly readable at full resolution
• VQ-02: No Overlap (8/8) - No overlapping text elements; legend is well-positioned and doesn't cover data
• VQ-03: Element Visibility (6/8) - Markers visible with white borders, confidence bands distinguishable but could have slightly higher contrast
• VQ-04: Color Accessibility (5/5) - Yellow/Blue/Cyan palette is colorblind-safe, avoids red-green combinations
• VQ-05: Layout Balance (5/5) - Plot fills canvas well, good proportions, balanced margins
• VQ-06: Axis Labels (2/2) - Both axes have descriptive labels with units ("Energy Consumption (GWh)", "Quarter")
• VQ-07: Grid & Legend (0/2) - Grid is appropriately subtle, but legend only shows main series - missing confidence band explanation

Spec Compliance (23/25 pts)

• SC-01: Plot Type (8/8) - Correct stacked area chart with confidence bands
• SC-02: Data Mapping (5/5) - X-axis correctly shows time periods, Y-axis shows cumulative stacked values
• SC-03: Required Features (4/5) - All main features present; legend could better identify what bands represent
• SC-04: Data Range (3/3) - All data visible within axis range
• SC-05: Legend Accuracy (2/2) - Legend correctly identifies Solar, Wind, Hydro
• SC-06: Title Format (1/2) - Title format is correct but uses middle-dot instead of bullet point (minor)

Data Quality (19/20 pts)

• DQ-01: Feature Coverage (7/8) - Shows seasonal variation, different magnitudes across sources, confidence bands of varying widths
• DQ-02: Realistic Context (7/7) - Renewable energy consumption is a realistic, neutral scenario with plausible seasonal patterns
• DQ-03: Appropriate Scale (5/5) - GWh values (15-50 range per source) are realistic for regional energy consumption

Code Quality (10/10 pts)

• CQ-01: KISS Structure (3/3) - Clean imports → data → chart config → series → export structure
• CQ-02: Reproducibility (3/3) - np.random.seed(42) set at the beginning
• CQ-03: Clean Imports (2/2) - All imports used (numpy, highcharts_core, selenium, tempfile, etc.)
• CQ-04: No Deprecated API (1/1) - Uses current highcharts-core 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 areaspline for smooth curves, arearange for confidence bands, gradient fills, shared tooltips, linkedTo for band association. Could leverage more interactive features.

Strengths

• Excellent implementation of stacked areas with confidence bands using Highcharts' areaspline and arearange series types
• Clean, professional visual appearance with good color choices and gradient fills
• Realistic data scenario with seasonal patterns that make sense for renewable energy
• Proper use of linkedTo to associate confidence bands with their parent series
• Good use of Highcharts-specific features like shared tooltips, crosshair, and gradient fills

Weaknesses

• Legend does not explain what the confidence bands represent (spec suggests including what bands represent)
• Confidence bands for stacked series show absolute ranges rather than symmetric bands around each layer (technically correct implementation but visually could be clearer)

Verdict: APPROVED