feat(altair): implement line-styled

[github-actions]

Implementation: line-styled - altair

Implements the altair version of line-styled.

File: plots/line-styled/implementations/altair.py

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

The plot displays a styled line chart showing monthly temperature readings from four weather stations (Coastal, Mountain, Valley, Highland) over 12 months (Jan-Dec). The chart uses distinct line styles: solid blue for Coastal, dashed yellow/gold for Mountain, dotted teal/green for Valley, and dash-dot coral/red for Highland. The X-axis shows months from January to December, and the Y-axis shows Temperature (°C) ranging from -4 to 40. All four lines follow a seasonal pattern peaking in summer months (July-August). The title "line-styled · altair · pyplots.ai" is displayed at the top. A legend in the upper-right corner identifies each station with its corresponding color and line style. A subtle grid with dashed lines aids readability.

Quality Score: 93/100

Criteria Checklist

Visual Quality (38/40 pts)

• VQ-01: Text Legibility (10/10) - Title at 28pt, axis labels at 22pt, tick labels at 18pt - all perfectly readable
• VQ-02: No Overlap (8/8) - No overlapping text elements, month labels well-spaced
• VQ-03: Element Visibility (8/8) - Lines are thick (strokeWidth=4), all styles clearly distinguishable
• VQ-04: Color Accessibility (5/5) - Uses Python Blue, Yellow, Teal, Coral - colorblind-friendly palette with distinct hues
• VQ-05: Layout Balance (5/5) - Plot fills canvas well, balanced margins, legend positioned appropriately
• VQ-06: Axis Labels (2/2) - "Month" and "Temperature (°C)" - descriptive with units
• VQ-07: Grid & Legend (0/2) - Grid is subtle (alpha 0.3), but legend symbols don't show line styles, only colors

Spec Compliance (25/25 pts)

• SC-01: Plot Type (8/8) - Correct line plot with multiple series
• SC-02: Data Mapping (5/5) - X=months, Y=temperature values, correctly assigned
• SC-03: Required Features (5/5) - All 4 line styles present (solid, dashed, dotted, dash-dot), legend included
• SC-04: Data Range (3/3) - Y-axis shows full range (-5 to 40), all data visible
• SC-05: Legend Accuracy (2/2) - Legend labels match data series correctly
• SC-06: Title Format (2/2) - Uses exact format "line-styled · altair · pyplots.ai"

Data Quality (20/20 pts)

• DQ-01: Feature Coverage (8/8) - Shows all 4 standard line styles (solid, dashed, dotted, dash-dot), seasonal patterns with variation
• DQ-02: Realistic Context (7/7) - Weather station temperature data is a real, neutral, comprehensible scenario
• DQ-03: Appropriate Scale (5/5) - Temperature values are realistic (-2°C to 35°C seasonal range)

Code Quality (10/10 pts)

• CQ-01: KISS Structure (3/3) - Simple script: imports → data → plot → save, no functions/classes
• CQ-02: Reproducibility (3/3) - Uses np.random.seed(42)
• CQ-03: Clean Imports (2/2) - Only used imports: altair, numpy, pandas
• CQ-04: No Deprecated API (1/1) - Uses current Altair API
• CQ-05: Output Correct (1/1) - Saves as plot.png and plot.html

Library Features (0/5 pts)

• LF-01: Uses distinctive library features (0/5) - Uses basic Altair mark_line and encode. Could leverage Altair's interactive features, tooltips, or selection mechanisms, but keeps it simple for styled line display

Strengths

• Excellent use of all four standard line styles (solid, dashed, dotted, dash-dot) clearly distinguishable
• Beautiful color palette with Python Blue and accessible complementary colors
• Professional typography with well-sized fonts for 4800x2700 output
• Realistic weather station temperature scenario with seasonal patterns
• Clean, KISS-compliant code structure following Altair best practices

Weaknesses

• Legend shows only color swatches, not the actual line styles (Altair limitation - strokeDash legend combined with color shows color only)
• No interactive features (tooltips, hover) which are Altair's distinctive strength

Verdict: APPROVED