feat(plotnine): implement streamline-basic

[github-actions]

Implementation: streamline-basic - plotnine

Implements the plotnine version of streamline-basic.

File: plots/streamline-basic/implementations/plotnine.py

Parent Issue: #2861

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

The plot displays a streamline visualization of a vortex vector field using plotnine. It shows 5 concentric circular streamlines at radii 0.5, 1.0, 1.5, 2.0, and 2.5, centered at the origin. Colors range from dark blue (#306998) at the inner circles to golden yellow (#FFD43B) at the outer circles, representing increasing flow speed (velocity magnitude = radius for a vortex). The title "streamline-basic · plotnine · pyplots.ai" appears at the top in bold black text. Axes are labeled "X Position" and "Y Position" with a clean minimal theme on white background. A color legend titled "Flow Speed" on the right shows the gradient from 0.5 to 2.5. The plot uses coord_fixed for a 1:1 aspect ratio.

Quality Score: 88/100

Criteria Checklist

Visual Quality (36/40 pts)

• VQ-01: Text Legibility (10/10) - Title is 24pt bold, axis labels 20pt, tick labels 16pt, legend text 14-18pt - all perfectly readable
• VQ-02: No Overlap (8/8) - No overlapping text elements
• VQ-03: Element Visibility (7/8) - Streamlines are clearly visible with good line width (1.2) and alpha (0.8), though slightly fewer visible features than ideal
• VQ-04: Color Accessibility (5/5) - Blue-to-yellow gradient is colorblind-safe (viridis-like)
• VQ-05: Layout Balance (3/5) - Good use of canvas but the circular plot in 16:9 frame leaves some empty space on sides; a 1:1 aspect ratio canvas would be more optimal
• VQ-06: Axis Labels (1/2) - Descriptive labels "X Position" and "Y Position" but no units
• VQ-07: Grid & Legend (2/2) - No visible grid (clean), legend well-placed on right

Spec Compliance (22/25 pts)

• SC-01: Plot Type (8/8) - Correct streamline visualization of vector field
• SC-02: Data Mapping (5/5) - X/Y correctly mapped, uses vortex field u=-y, v=x as spec suggests
• SC-03: Required Features (3/5) - Shows streamlines and color-coded velocity magnitude, but streamlines appear as perfect circles rather than showing flow direction/starting points distribution as spec notes
• SC-04: Data Range (3/3) - Axes show full -3 to 3 range adequately
• SC-05: Legend Accuracy (2/2) - Legend correctly labeled "Flow Speed"
• SC-06: Title Format (1/2) - Uses correct format but middle dot may render inconsistently

Data Quality (17/20 pts)

• DQ-01: Feature Coverage (6/8) - Shows concentric circular flow pattern but all streamlines are similar circles - doesn't show flow direction indicators or varied topology
• DQ-02: Realistic Context (7/7) - Vortex flow is a classic fluid dynamics example, neutral scientific topic
• DQ-03: Appropriate Scale (4/5) - Values are appropriate for normalized coordinates, though domain could have more context

Code Quality (8/10 pts)

• CQ-01: KISS Structure (1/3) - Has a helper function velocity_field which violates KISS principle of no functions/classes
• CQ-02: Reproducibility (3/3) - Uses np.random.seed(42)
• CQ-03: Clean Imports (2/2) - All imports are used
• CQ-04: No Deprecated API (1/1) - Uses current APIs
• CQ-05: Output Correct (1/1) - Saves as plot.png

Library Features (5/5 pts)

• LF-01: Uses distinctive library features (5/5) - Good use of plotnine's grammar of graphics: geom_path with grouping, scale_color_gradient, coord_fixed, theme customization

Strengths

• Excellent use of plotnine's geom_path with proper grouping by streamline ID for trajectory visualization
• Creative solution using scipy.integrate.solve_ivp to compute streamlines since plotnine lacks native streamline support
• Beautiful blue-to-yellow color gradient that is colorblind-accessible
• Proper use of coord_fixed for 1:1 aspect ratio appropriate for vector field visualization
• Clean, professional appearance with well-sized text elements

Weaknesses

• Contains a helper function velocity_field which violates the KISS principle (no functions/classes rule)
• Streamlines don't indicate flow direction (no arrows or visual cues showing which way the flow goes)
• 16:9 aspect ratio leaves empty horizontal space for this circular pattern; 1:1 canvas would be more appropriate
• All streamlines are nearly perfect circles with similar appearance - could benefit from more varied starting points to show field topology better

Verdict: REJECTED

[github-actions]

🔧 Repair Attempt 1/3

Applied fixes based on AI review feedback.

Status: Repair completed, re-triggering review...

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🤖 impl-repair

[claude]

AI Review - Attempt 2/3

Image Description

The plot displays a vortex flow field visualization with concentric circular streamlines centered at the origin. The streamlines form nested circles ranging from radius ~0.5 to ~3, demonstrating counter-clockwise rotation as indicated by small arrow markers along each streamline. Color encoding transitions from blue (low speed ~1) at the center to yellow (high speed ~3) at outer radii, matching the vortex velocity relationship (speed = radius). The plot uses a square 1:1 canvas with axes ranging from -3 to 3 on both X and Y. The title "streamline-basic · plotnine · pyplots.ai" appears at the top in bold. Axis labels show "X Position" and "Y Position". A color bar legend labeled "Flow Speed" appears on the right side. The background is white with subtle grid lines.

Quality Score: 90/100

Criteria Checklist

Visual Quality (36/40 pts)

• VQ-01: Text Legibility (10/10) - Title 24pt bold, axis titles 20pt, tick labels 16pt, all clearly readable
• VQ-02: No Overlap (8/8) - No overlapping text elements
• VQ-03: Element Visibility (8/8) - Streamlines sized appropriately at 1.2 width, alpha 0.8 provides good visibility
• VQ-04: Color Accessibility (5/5) - Blue-to-yellow (viridis-like) gradient is colorblind-safe
• VQ-05: Layout Balance (5/5) - Square 1:1 aspect ratio perfectly suits circular streamlines, good canvas utilization
• VQ-06: Axis Labels (1/2) - Labels are descriptive but lack units
• VQ-07: Grid & Legend (2/2) - Subtle grid, well-placed legend on right

Spec Compliance (23/25 pts)

• SC-01: Plot Type (8/8) - Correct streamline visualization using continuous paths
• SC-02: Data Mapping (5/5) - X/Y grid with u=-y, v=x vortex field correctly mapped
• SC-03: Required Features (5/5) - Smooth streamlines, color-coded velocity, directional indicators
• SC-04: Data Range (3/3) - Full -3 to 3 range visible on both axes
• SC-05: Legend Accuracy (2/2) - "Flow Speed" legend correctly describes color mapping
• SC-06: Title Format (0/2) - Uses correct format: "streamline-basic · plotnine · pyplots.ai"

Wait, let me recheck SC-06 - the title IS correct.

• SC-06: Title Format (2/2) - Correct format: "streamline-basic · plotnine · pyplots.ai"

Data Quality (19/20 pts)

• DQ-01: Feature Coverage (8/8) - Shows full vortex topology with concentric circles, varying speeds
• DQ-02: Realistic Context (6/7) - Vortex flow is plausible physics scenario
• DQ-03: Appropriate Scale (5/5) - Values -3 to 3 are sensible for a normalized vector field

Code Quality (9/10 pts)

• CQ-01: KISS Structure (2/3) - Uses solve_ivp with lambda for integration (borderline complexity but acceptable)
• CQ-02: Reproducibility (3/3) - np.random.seed(42) set
• CQ-03: Clean Imports (2/2) - All imports used
• CQ-04: No Deprecated API (1/1) - Current APIs
• CQ-05: Output Correct (1/1) - Saves as plot.png

Library Features (3/5 pts)

• LF-01: Uses distinctive library features (3/5) - Uses ggplot grammar with geom_path and geom_point, but scipy handles the actual streamline computation rather than plotnine-native features

Strengths

• Excellent vortex flow visualization with concentric circular streamlines that clearly demonstrate field topology
• Effective color gradient (blue to yellow) encoding flow speed with values increasing toward the outer regions
• Arrow markers positioned along streamlines clearly indicate counter-clockwise flow direction
• Well-balanced 1:1 aspect ratio canvas that perfectly suits circular streamline patterns
• Good use of plotnine grammar of graphics with geom_path for streamlines and geom_point for directional arrows

Weaknesses

• Axis labels could include units or more descriptive context (e.g., meters, arbitrary units)

Verdict: APPROVED