D3 Tree with Multiple Parents
This example visualizes a D3 tree layout with multiple parents, allowing nodes to be shared between different branches of a hierarchical structure. The graph displays data from a JSON file, with nodes representing concepts like "Government of the United States" and "Stock market" linking to common children such as "Supply and demand" and "Foreign worker." The code uses `d3.tree`, `d3.hierarchy`, and `d3.linkHorizontal` to generate the layout, while underscore.js handles deduplication of nodes by ID and recalculation of their positions. SVG paths and text elements render the links and labels, with zoom and transition animations applied throughout.