[flowmap-origin-destination] Origin-Destination Flow Map

[MarkusNeusinger]

Description

A map showing flows between origin and destination points with curved lines, where line thickness represents flow magnitude.

Applications

• Migration flow visualization
• Trade route analysis
• Commuter pattern mapping
• Supply chain logistics

Data

• origin_lat, origin_lon (numeric) - Origin coordinates
• dest_lat, dest_lon (numeric) - Destination coordinates
• flow (numeric) - Flow magnitude
• Size: 20-200 flows

Notes

• Curved arcs (Bezier or great circle)
• Line width proportional to flow volume
• Color gradient for direction or magnitude
• Transparency for overlapping flows
• Optional animation showing flow direction

[claude]

✅ Spec ID: flowmap-origin-destination

Rationale: This is a distinct geographic flow visualization combining map projection with origin-destination arcs - not covered by existing specs like sankey-basic (categorical flows), chord-basic (circular layout), or scatter-map-geographic (point-only).

Add label approved to begin generation.

[github-actions]

✅ Specification Ready: flowmap-origin-destination

PR: #3776

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specification.md

flowmap-origin-destination: Origin-Destination Flow Map

Description

An origin-destination flow map visualizes movement or transfer between geographic locations using curved arcs overlaid on a map. Each arc connects an origin point to a destination point, with line thickness proportional to the flow magnitude. This visualization excels at revealing spatial patterns in migration, trade, or travel data, making it easy to identify major corridors, hub locations, and directional imbalances in movement between places.

Applications

• Visualizing international migration flows showing population movement between countries or regions
• Analyzing trade routes displaying import/export volumes between ports or economic centers
• Mapping commuter patterns showing daily travel flows between residential areas and employment centers
• Displaying supply chain logistics illustrating shipment volumes between distribution centers and retail locations

Data

• origin_lat (numeric) - Latitude coordinate of flow origin (-90 to 90)
• origin_lon (numeric) - Longitude coordinate of flow origin (-180 to 180)
• dest_lat (numeric) - Latitude coordinate of flow destination (-90 to 90)
• dest_lon (numeric) - Longitude coordinate of flow destination (-180 to 180)
• flow (numeric) - Flow magnitude or volume (determines arc thickness)
• origin_name (string, optional) - Label for origin location
• dest_name (string, optional) - Label for destination location
• Size: 20-200 flows (fewer flows for clarity; too many obscure patterns)
• Example: Migration flows between world capitals, trade volumes between major ports

Notes

• Use curved arcs (Bezier curves or great circle paths) to connect origin and destination points
• Line width should be proportional to flow magnitude for visual comparison
• Apply transparency (alpha 0.4-0.7) to handle overlapping arcs in dense flow networks
• Consider using a color gradient to encode flow direction or magnitude
• Include a basemap with country boundaries or coastlines for geographic context
• For interactive libraries, add hover tooltips showing exact flow values and location names
• Optionally animate arcs to show flow direction using moving particles or progressive drawing

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Next: Add approved label to merge this specification to main.

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🤖 spec-create workflow

[github-actions]

🚀 Specification Merged!

Specification: flowmap-origin-destination
PR: #3776 (merged)

The specification is now in main and synced to PostgreSQL.

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Next: Add generate:{library} labels to start generating implementations.

Available libraries: matplotlib, seaborn, plotly, bokeh, altair, plotnine, pygal, highcharts, letsplot

Or use workflow dispatch for bulk operations.

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🤖 spec-create workflow