feat(highcharts): implement sn-curve-basic

[github-actions]

Implementation: sn-curve-basic - highcharts

Implements the highcharts version of sn-curve-basic.

File: plots/sn-curve-basic/implementations/highcharts.py

Parent Issue: #3826

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

The plot displays an S-N curve (Wöhler curve) for fatigue analysis with a white background. The x-axis shows "Number of Cycles to Failure (N)" on a logarithmic scale from 100 to 100M, and the y-axis shows "Stress Amplitude (MPa)" on a logarithmic scale from 140 to 600. Blue circular markers represent test data points scattered around a yellow Basquin fit line that slopes downward from left to right. Three horizontal dashed reference lines are visible: red at 500 MPa (Ultimate Strength), orange at 350 MPa (Yield Strength), and green at 200 MPa (Endurance Limit), each with labels on the right side. Three italic region annotations appear: "Low-Cycle Fatigue" in the upper left, "High-Cycle Fatigue" in the middle, and "Infinite Life" in the lower right. A legend in the upper right shows "Test Data" and "Basquin Fit". The title "sn-curve-basic · highcharts · pyplots.ai" is centered at the top.

Quality Score: 91/100

Criteria Checklist

Visual Quality (36/40 pts)

• VQ-01: Text Legibility (9/10) - Title, axis labels, and tick marks are readable; reference line labels are slightly small but legible
• VQ-02: No Overlap (8/8) - No overlapping text elements; all labels and annotations are clearly separated
• VQ-03: Element Visibility (7/8) - Markers are appropriately sized for the data density (~35 points); good alpha/opacity
• VQ-04: Color Accessibility (5/5) - Blue/yellow/red/orange/green palette is colorblind-safe; no red-green only distinctions
• VQ-05: Layout Balance (5/5) - Good canvas utilization; plot fills most of the space with balanced margins
• VQ-06: Axis Labels (2/2) - Descriptive labels with units: "Stress Amplitude (MPa)" and "Number of Cycles to Failure (N)"
• VQ-07: Grid & Legend (0/2) - Grid lines are too prominent (not subtle), legend could be better positioned closer to data

Spec Compliance (25/25 pts)

• SC-01: Plot Type (8/8) - Correct S-N curve with scatter points and fitted line
• SC-02: Data Mapping (5/5) - X=cycles (log), Y=stress (log) correctly assigned
• SC-03: Required Features (5/5) - All spec features present: logarithmic axes, reference lines (Ultimate, Yield, Endurance), three fatigue regions, Basquin fit
• SC-04: Data Range (3/3) - Full data range visible from 100 to 100M cycles
• SC-05: Legend Accuracy (2/2) - Legend correctly shows "Test Data" and "Basquin Fit"
• SC-06: Title Format (2/2) - Correct format: "sn-curve-basic · highcharts · pyplots.ai"

Data Quality (18/20 pts)

• DQ-01: Feature Coverage (7/8) - Shows scatter, fitted curve, three regions, and reference lines; good variety in test points
• DQ-02: Realistic Context (7/7) - Steel fatigue testing is a real engineering scenario with realistic stress values (200-500 MPa)
• DQ-03: Appropriate Scale (4/5) - Values are realistic for structural steel; minor issue: data points near 450 MPa seem sparse

Code Quality (9/10 pts)

• CQ-01: KISS Structure (3/3) - Linear flow: imports → data → plot → save; no functions/classes
• CQ-02: Reproducibility (3/3) - np.random.seed(42) is set
• CQ-03: Clean Imports (1/2) - Imports LineSeries from area module (unconventional but works)
• CQ-04: No Deprecated API (1/1) - Uses current Highcharts API
• CQ-05: Output Correct (1/1) - Saves as plot.png and plot.html

Library Features (3/5 pts)

• LF-01: Distinctive Features (3/5) - Uses Highcharts annotations, plotLines, and logarithmic axes well; could leverage more interactive features

Strengths

• Excellent implementation of all required S-N curve features including reference lines and region annotations
• Good use of Highcharts-specific features: plotLines for reference lines, annotations module for region labels
• Clean data generation using Basquin equation with realistic scatter
• Proper logarithmic scales on both axes as required by spec
• Colorblind-safe color palette

Weaknesses

• Grid lines are too prominent (solid dash style visible) - should be more subtle with lower opacity
• LineSeries import from area module is unconventional (should import from line module)

Verdict: APPROVED