feat(highcharts): implement smith-chart-basic

[github-actions]

Implementation: smith-chart-basic - highcharts

Implements the highcharts version of smith-chart-basic.

File: plots/smith-chart-basic/implementations/highcharts.py

Parent Issue: #3792

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

The plot displays a Smith chart for RF/impedance visualization with a square 1:1 aspect ratio layout. The chart shows:

• Title: "smith-chart-basic · highcharts · pyplots.ai" at the top in bold black text
• Subtitle: "Antenna Impedance Sweep 1-6 GHz (Z₀ = 50Ω)" below the title
• Unit Circle: A solid dark gray circle marking |Γ| = 1 (the boundary of total reflection)
• Resistance Circles: Blue dotted circles (R=0, 0.2, 0.5, 1, 2, 5) centered along the horizontal axis
• Reactance Arcs: Gold/tan dotted arcs (X=±0.2, ±0.5, ±1, ±2) curving from the right edge
• VSWR Circles: Three dashed concentric circles in purple, cyan, and brown for VSWR=1.5, 2.0, 3.0
• Matched Point: A green diamond marker at the center (0,0) representing Z=Z₀
• Impedance Locus: A red connected curve with circular markers showing the frequency sweep trajectory from 1-6 GHz
• Frequency Labels: Boxed annotations at 1.0, 2.3, 3.6, 4.8, and 6.0 GHz along the impedance curve
• Axes: Real(Γ) on x-axis and Imag(Γ) on y-axis, ranging from -1.2 to 1.2
• Legend: Positioned at bottom showing VSWR values, Matched point, and Impedance Locus series
• Colors: Colorblind-safe palette with blue, gold, red, purple, cyan, brown, green

Quality Score: 91/100

Criteria Checklist

Visual Quality (36/40 pts)

• VQ-01: Text Legibility (10/10) - Title, subtitle, axis labels, tick marks, frequency annotations all clearly readable
• VQ-02: No Overlap (8/8) - No overlapping text elements; frequency annotations well-spaced
• VQ-03: Element Visibility (7/8) - Markers and lines visible; grid lines could be slightly more subtle but acceptable
• VQ-04: Color Accessibility (5/5) - Excellent colorblind-safe palette avoiding red-green conflicts
• VQ-05: Layout Balance (3/5) - Chart well-centered but the Y-axis extends beyond the unit circle unnecessarily (±1.5 instead of ±1.2)
• VQ-06: Axis Labels (2/2) - Descriptive labels "Real(Γ)" and "Imag(Γ)" with proper Greek symbols
• VQ-07: Grid & Legend (1/2) - Legend is present and readable; grid lines (constant R/X) are subtle but legend is cramped at bottom

Spec Compliance (24/25 pts)

• SC-01: Plot Type (8/8) - Correct Smith chart implementation with proper polar impedance representation
• SC-02: Data Mapping (5/5) - Impedance correctly normalized and converted to reflection coefficient Γ
• SC-03: Required Features (5/5) - All spec features present: resistance circles, reactance arcs, impedance locus, frequency labels, VSWR circles, matched center
• SC-04: Data Range (3/3) - Full frequency sweep visible within chart boundaries
• SC-05: Legend Accuracy (1/2) - Legend labels correct but not all grid elements labeled (R/X values not in legend, which is appropriate)
• SC-06: Title Format (2/2) - Correct format "smith-chart-basic · highcharts · pyplots.ai"

Data Quality (18/20 pts)

• DQ-01: Feature Coverage (7/8) - Shows impedance variation across frequency, resonance behavior, and VSWR context; could show more dramatic impedance variation
• DQ-02: Realistic Context (7/7) - Excellent realistic antenna scenario with resonance around 3.5 GHz and proper Q factor modeling
• DQ-03: Appropriate Scale (4/5) - Realistic 50Ω reference, 1-6 GHz range; impedance values are plausible but locus trajectory is somewhat compact

Code Quality (8/10 pts)

• CQ-01: KISS Structure (1/3) - Uses helper functions (resistance_circle, reactance_arc) which deviates from KISS principle
• CQ-02: Reproducibility (3/3) - Fixed seed np.random.seed(42) used
• CQ-03: Clean Imports (2/2) - All imports are used
• CQ-04: No Deprecated API (1/1) - Modern API usage
• CQ-05: Output Correct (1/1) - Saves as plot.png and plot.html

Library Features (5/5 pts)

• LF-01: Uses distinctive library features (5/5) - Excellent use of Highcharts: annotations, series with markers and lines, multiple series composition, dash styles, interactive HTML export

Strengths

• Excellent Smith chart implementation with proper RF engineering context and terminology
• Complete grid with constant resistance circles and constant reactance arcs
• Colorblind-safe palette with good visual distinction between elements
• Frequency labels as boxed annotations along the impedance curve provide valuable context
• VSWR circles add useful engineering reference
• High-resolution 3600×3600 square format appropriate for circular chart
• Proper impedance normalization and reflection coefficient calculation

Weaknesses

• Code uses helper functions (resistance_circle, reactance_arc) instead of inline code, violating KISS principle
• Y-axis range extends to ±1.5 when ±1.2 would be sufficient, causing some wasted whitespace
• Legend at bottom is somewhat cramped and could be better positioned

Verdict: APPROVED