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how to remove path between two nodes in D3js Tidy tree?


I am so new with D3js

I have a Tidy Tree chart like this

 const data = {
                "name": "tree",
                "id":0,
                "children": [
                    {
                        "name": "A",
                         "id" :1,
                        "children": [
                            {
                                "name": "B",
                                 "id" :2,
  
                                "children": [
                                    { "name": "C", "id": 3 },
                                ]
                            },
                            {
                                "name": "H",
                                 "id" :4,

                                "children": [
                                    { "name": "D", "id": 5 },
                                    { "name": "E", "id": 6 },
                                    { "name": "F", "id": 7 },
                                ]
                            },
                        ]
                    }
                ]
            }

            const width = 928;

            // Compute the tree height; this approach will allow the height of the
            // SVG to scale according to the breadth (width) of the tree layout.
            const root = d3.hierarchy(data);
            const dx = 10;
            const dy = width / (root.height + 1);

            // Create a tree layout.
            const tree = d3.tree().nodeSize([dx, dy]);

            // Sort the tree and apply the layout.
            root.sort((a, b) => d3.ascending(a.data.name, b.data.name));
            tree(root);

            // Compute the extent of the tree. Note that x and y are swapped here
            // because in the tree layout, x is the breadth, but when displayed, the
            // tree extends right rather than down.
            let x0 = Infinity;
            let x1 = -x0;
            root.each(d => {
                if (d.x > x1) x1 = d.x;
                if (d.x < x0) x0 = d.x;
            });

            // Compute the adjusted height of the tree.
            const height = x1 - x0 + dx * 2;

            const svg = d3.select("svg")
                .attr("width", width)
                .attr("height", height)
                .attr("viewBox", [-dy / 3, x0 - dx, width, height])
                .attr("style", "max-width: 100%; height: auto; font: 10px sans-serif;");

            const link = svg.append("g")
                .attr("fill", "none")
                .attr("stroke", "#555")
                .attr("stroke-opacity", 0.4)
                .attr("stroke-width", 1.5)
              
              link
                .selectAll()
                .data(root.links())
                .join("path")
                .attr("d", d3.linkHorizontal()
                    .x(d => d.y)
                    .y(d => d.x));

            const node = svg.append("g")
                .attr("stroke-linejoin", "round")
                .attr("stroke-width", 3)
                .selectAll()
                .data(root.descendants())
                .join("g")
                .attr("transform", d => `translate(${d.y},${d.x})`)

            node.append("circle")
                .attr("fill", d => d.children ? "#555" : "#999")
                .attr("r", 5.5)

            node.append("text")
                .attr("dy", "0.31em")
                .attr("x", d => d.children ? -6 : 6)
                .attr("text-anchor", d => d.children ? "end" : "start")
                .text(d => d.data.name)
                .clone(true).lower()
                .attr("stroke", "white");

            d3.selectAll("circle").on("contextmenu", (event) => {
                this.selectedNode = event.srcElement.__data__.data
            });

            const connectNodes = (t, f) => {
              let to = null, fr = null;
              node.each( d => {
                if (d.data.name === t) to = d;
                if (d.data.name === f) fr = d;
              });
              if (to && fr){
                link.append("path")
                  .attr("d", "M" + to.y + "," + to.x + "L" + fr.y + "," + fr.x)
                  .attr("fill", "none")
                  .attr("stroke", "red"); 
              }             
            };
            connectNodes("B", "D");
<!doctype html>

<html>
  <head>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/d3/7.8.5/d3.js"></script>

  </head>

  <body>
    <svg></svg>

  </body>
</html>

now I need to remove link between H and F enter image description here How can I do it ?


Solution

  • If you are looking to leave the chart and simply remove connecting lines, here is how I would do it:

    const data = {
      "name": "tree",
      "children": [{
        "name": "A",
        "children": [{
            "name": "B",
            "children": [{
              "name": "C",
              "size": 3938
            }, ]
          },
          {
            "name": "H",
            "children": [{
                "name": "D",
                "size": 3534
              },
              {
                "name": "E",
                "size": 5731
              },
              {
                "name": "F",
                "size": 7840
              },
            ]
          },
        ]
      }]
    }
    
    const width = 928;
    
    // Compute the tree height; this approach will allow the height of the
    // SVG to scale according to the breadth (width) of the tree layout.
    const root = d3.hierarchy(data);
    const dx = 10;
    const dy = width / (root.height + 1);
    
    // Create a tree layout.
    const tree = d3.tree().nodeSize([dx, dy]);
    
    // Sort the tree and apply the layout.
    root.sort((a, b) => d3.ascending(a.data.name, b.data.name));
    tree(root);
    
    // Compute the extent of the tree. Note that x and y are swapped here
    // because in the tree layout, x is the breadth, but when displayed, the
    // tree extends right rather than down.
    let x0 = Infinity;
    let x1 = -x0;
    root.each(d => {
      if (d.x > x1) x1 = d.x;
      if (d.x < x0) x0 = d.x;
    });
    
    // Compute the adjusted height of the tree.
    const height = x1 - x0 + dx * 2;
    
    const svg = d3.select("svg")
      .attr("width", width)
      .attr("height", height)
      .attr("viewBox", [-dy / 3, x0 - dx, width, height])
      .attr("style", "max-width: 100%; height: auto; font: 10px sans-serif;");
    
    const link = svg.append("g")
      .attr("fill", "none")
      .attr("stroke", "#555")
      .attr("stroke-opacity", 0.4)
      .attr("stroke-width", 1.5)
    
    link
      .selectAll()
      .data(root.links())
      .join("path")
      .attr("d", d3.linkHorizontal()
        .x(d => d.y)
        .y(d => d.x))
      .attr("id", d =>
        d.source.data.name + "-" + d.target.data.name
      );
    
    const node = svg.append("g")
      .attr("stroke-linejoin", "round")
      .attr("stroke-width", 3)
      .selectAll()
      .data(root.descendants())
      .join("g")
      .attr("transform", d => `translate(${d.y},${d.x})`)
    
    node.append("circle")
      .attr("fill", d => d.children ? "#555" : "#999")
      .attr("r", 5.5)
    
    node.append("text")
      .attr("dy", "0.31em")
      .attr("x", d => d.children ? -6 : 6)
      .attr("text-anchor", d => d.children ? "end" : "start")
      .text(d => d.data.name)
      .clone(true).lower()
      .attr("stroke", "white");
    
    d3.selectAll("circle").on("contextmenu", (event) => {
      this.selectedNode = event.srcElement.__data__.data
    });
    
    const connectNodes = (t, f) => {
      let to = null,
        fr = null;
      node.each(d => {
        if (d.data.name === t) to = d;
        if (d.data.name === f) fr = d;
      });
      if (to && fr) {
        link.append("path")
          .attr("d", "M" + to.y + "," + to.x + "L" + fr.y + "," + fr.x)
          .attr("id", to.data.name + "-" + fr.data.name)
          .attr("fill", "none")
          .attr("stroke", "red");
      }
    };
    connectNodes("B", "D");
    
    const removeConnection = (t, f) => {
      d3.select("#" + t + "-" + f).remove();
    }
    removeConnection("H", "F");
    <!doctype html>
    
    <html>
    
    <head>
      <script src="https://cdnjs.cloudflare.com/ajax/libs/d3/7.8.5/d3.js"></script>
    
    </head>
    
    <body>
      <svg></svg>
    
    </body>
    
    </html>