feat(plotly): implement contour-density

[github-actions]

Implementation: contour-density - plotly

Implements the plotly version of contour-density.

File: plots/contour-density/implementations/plotly.py

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

The plot displays a density contour visualization with three distinct clusters. The colorscale transitions from transparent/cream at low density through yellow (#FFD43B) at medium density to dark blue (#306998/#1a3d5c) at high density. Three cluster centers are visible: one at approximately (2, 3), another at (5, 5), and a third at (7, 2.5). Semi-transparent scatter points are overlaid showing the underlying data distribution. The title "contour-density · plotly · pyplots.ai" is centered at the top. Axis labels "X Variable" and "Y Variable" are clearly displayed. A colorbar on the right shows the density scale from 0 to ~45. The background is white with subtle grid lines.

Quality Score: 92/100

Criteria Checklist

Visual Quality (37/40 pts)

• VQ-01: Text Legibility (10/10) - Title at 32pt, axis labels at 24pt, tick labels at 18pt - all perfectly readable
• VQ-02: No Overlap (8/8) - No overlapping text elements anywhere
• VQ-03: Element Visibility (8/8) - Contour fills are well-defined, scatter overlay uses appropriate alpha (0.3) for 500 points
• VQ-04: Color Accessibility (5/5) - Yellow-to-blue colorscale is colorblind-safe, good contrast
• VQ-05: Layout Balance (5/5) - Plot fills canvas well with balanced margins
• VQ-06: Axis Labels (1/2) - Descriptive labels but generic (no units or specific context)
• VQ-07: Grid & Legend (0/2) - Colorbar well-placed, but grid alpha at 0.1 is too subtle/barely visible

Spec Compliance (25/25 pts)

• SC-01: Plot Type (8/8) - Correct density contour plot using Histogram2dContour
• SC-02: Data Mapping (5/5) - X/Y correctly assigned to continuous variables
• SC-03: Required Features (5/5) - Has contour lines, filled contours, scatter overlay as spec suggests
• SC-04: Data Range (3/3) - Axes show all data points without clipping
• SC-05: Legend Accuracy (2/2) - Colorbar correctly labeled as "Density"
• SC-06: Title Format (2/2) - Uses exact format "contour-density · plotly · pyplots.ai"

Data Quality (18/20 pts)

• DQ-01: Feature Coverage (8/8) - Shows multiple clusters with varying densities, demonstrates core use case of finding density patterns
• DQ-02: Realistic Context (5/7) - Plausible bivariate data but generic (not tied to real-world scenario like scientific measurements)
• DQ-03: Appropriate Scale (5/5) - Values in sensible range (0-8), appropriate for demonstration

Code Quality (10/10 pts)

• CQ-01: KISS Structure (3/3) - Clean imports → data → plot → save structure, no functions/classes
• CQ-02: Reproducibility (3/3) - np.random.seed(42) set correctly
• CQ-03: Clean Imports (2/2) - Only numpy and plotly.graph_objects used, both necessary
• CQ-04: No Deprecated API (1/1) - Uses current Plotly APIs
• CQ-05: Output Correct (1/1) - Saves as plot.png with correct dimensions

Library Features (2/5 pts)

• LF-01: Uses distinctive library features (2/5) - Uses Histogram2dContour which is Plotly-specific, but does not leverage Plotly's interactive features in the static output (hover tooltips would enhance HTML version)

Strengths

• Excellent use of filled contours with custom colorscale transitioning from transparent white to yellow to blue
• Smart combination of density contours with scatter point overlay provides context as recommended in spec
• Three distinct clusters effectively demonstrate the plot's purpose of finding density patterns
• Clean code structure following KISS principles
• Proper font sizing for 4800x2700 output (scale=3)

Weaknesses

• Axis labels are generic ("X Variable", "Y Variable") rather than tied to a realistic context
• Grid lines are too subtle (alpha 0.1) - consider alpha 0.2-0.3 for better visibility

Verdict: APPROVED