javascript - d3.js Sankey 使用命名节点

Question

我使用 d3.js 框架创建了第一个桑基图。

我的节点和链接具有以下结构:

"nodes": [{
     "name" : "TestViewCode",
     "id" : "environment_score"
}],

"links" : [
  {
     "source" : 9,
     "value" : 0.00283706180951111,
     "target" : 0
  }]

以及以下 JavaScript 代码:

<script>
  var colors = {
        'environment':         '#edbd00',
        'social':              '#367d85',
        'animals':             '#97ba4c',
        'health':              '#f5662b',
        'research_ingredient': '#3f3e47',
        'fallback':            '#9f9fa3'
      };


  d3.json("file:///Users/.../Desktop/jsonpg.json", function(error, json) {
    var chart = d3.select("#chart").append("svg").chart("Sankey.Path");


    chart
      .name(label)
      .colorNodes(function(name, node) {
        return color(node, 1) || colors.fallback;
      })


      .colorLinks(function(link) {
        return color(link.source, 4) || color(link.target, 1) || colors.fallback;
      })
      .nodeWidth(15)
      .nodePadding(10)
      .spread(true)
      .iterations(0)
      .draw(json);

    function label(node) {
      return node.name.replace(/\s*\(.*?\)$/, '');
    }

    function color(node, depth) {
      var id = node.id.replace(/(_score)?(_\d+)?$/, '');

      if (colors[id]) {
        return colors[id];
      } else if (depth > 0 && node.targetLinks && node.targetLinks.length == 1) {
        return color(node.targetLinks[0].source, depth-1);
      } else {
        return null;
      }
    }

  });

</script>

sankey.js

d3.sankey = function() {
  var sankey = {},
      nodeWidth = 24,
      nodePadding = 8,
      size = [1, 1],
      nodes = [],
      links = [];

  sankey.nodeWidth = function(_) {
    if (!arguments.length) return nodeWidth;
    nodeWidth = +_;
    return sankey;
  };

  sankey.nodePadding = function(_) {
    if (!arguments.length) return nodePadding;
    nodePadding = +_;
    return sankey;
  };

  sankey.nodes = function(_) {
    if (!arguments.length) return nodes;
    nodes = _;
    return sankey;
  };

  sankey.links = function(_) {
    if (!arguments.length) return links;
    links = _;
    return sankey;
  };

  sankey.size = function(_) {
    if (!arguments.length) return size;
    size = _;
    return sankey;
  };

  sankey.layout = function(iterations) {
    computeNodeLinks();
    computeNodeValues();
    computeNodeBreadths();
    computeNodeDepths(iterations);
    computeLinkDepths();
    return sankey;
  };

  sankey.relayout = function() {
    computeLinkDepths();
    return sankey;
  };

  sankey.link = function() {
    var curvature = .5;

    function link(d) {
      var x0 = d.source.x + d.source.dx,
          x1 = d.target.x,
          xi = d3.interpolateNumber(x0, x1),
          x2 = xi(curvature),
          x3 = xi(1 - curvature),
          y0 = d.source.y + d.sy + d.dy / 2,
          y1 = d.target.y + d.ty + d.dy / 2;
      return "M" + x0 + "," + y0
           + "C" + x2 + "," + y0
           + " " + x3 + "," + y1
           + " " + x1 + "," + y1;
    }

    link.curvature = function(_) {
      if (!arguments.length) return curvature;
      curvature = +_;
      return link;
    };

    return link;
  };

  // Populate the sourceLinks and targetLinks for each node.
  // Also, if the source and target are not objects, assume they are indices.
  function computeNodeLinks() {
    nodes.forEach(function(node) {
      node.sourceLinks = [];
      node.targetLinks = [];
    });
    links.forEach(function(link) {
      var source = link.source,
          target = link.target;
      if (typeof source === "number") source = link.source = nodes[link.source];
      if (typeof target === "number") target = link.target = nodes[link.target];
      source.sourceLinks.push(link);
      target.targetLinks.push(link);
    });
  }

  // Compute the value (size) of each node by summing the associated links.
  function computeNodeValues() {
    nodes.forEach(function(node) {
      node.value = Math.max(
        d3.sum(node.sourceLinks, value),
        d3.sum(node.targetLinks, value)
      );
    });
  }

  // Iteratively assign the breadth (x-position) for each node.
  // Nodes are assigned the maximum breadth of incoming neighbors plus one;
  // nodes with no incoming links are assigned breadth zero, while
  // nodes with no outgoing links are assigned the maximum breadth.
  function computeNodeBreadths() {
    var remainingNodes = nodes,
        nextNodes,
        x = 0;

    while (remainingNodes.length) {
      nextNodes = [];
      remainingNodes.forEach(function(node) {
        node.x = x;
        node.dx = nodeWidth;
        node.sourceLinks.forEach(function(link) {
          nextNodes.push(link.target);
        });
      });
      remainingNodes = nextNodes;
      ++x;
    }

    //
    moveSinksRight(x);
    scaleNodeBreadths((size[0] - nodeWidth) / (x - 1));
  }

  function moveSourcesRight() {
    nodes.forEach(function(node) {
      if (!node.targetLinks.length) {
        node.x = d3.min(node.sourceLinks, function(d) { return d.target.x; }) - 1;
      }
    });
  }

  function moveSinksRight(x) {
    nodes.forEach(function(node) {
      if (!node.sourceLinks.length) {
        node.x = x - 1;
      }
    });
  }

  function scaleNodeBreadths(kx) {
    nodes.forEach(function(node) {
      node.x *= kx;
    });
  }

  function computeNodeDepths(iterations) {
    var nodesByBreadth = d3.nest()
        .key(function(d) { return d.x; })
        .sortKeys(d3.ascending)
        .entries(nodes)
        .map(function(d) { return d.values; });

    //
    initializeNodeDepth();
    resolveCollisions();
    for (var alpha = 1; iterations > 0; --iterations) {
      relaxRightToLeft(alpha *= .99);
      resolveCollisions();
      relaxLeftToRight(alpha);
      resolveCollisions();
    }

    function initializeNodeDepth() {
      var ky = d3.min(nodesByBreadth, function(nodes) {
        return (size[1] - (nodes.length - 1) * nodePadding) / d3.sum(nodes, value);
      });

      nodesByBreadth.forEach(function(nodes) {
        nodes.forEach(function(node, i) {
          node.y = i;
          node.dy = node.value * ky;
        });
      });

      links.forEach(function(link) {
        link.dy = link.value * ky;
      });
    }

    function relaxLeftToRight(alpha) {
      nodesByBreadth.forEach(function(nodes, breadth) {
        nodes.forEach(function(node) {
          if (node.targetLinks.length) {
            var y = d3.sum(node.targetLinks, weightedSource) / d3.sum(node.targetLinks, value);
            node.y += (y - center(node)) * alpha;
          }
        });
      });

      function weightedSource(link) {
        return center(link.source) * link.value;
      }
    }

    function relaxRightToLeft(alpha) {
      nodesByBreadth.slice().reverse().forEach(function(nodes) {
        nodes.forEach(function(node) {
          if (node.sourceLinks.length) {
            var y = d3.sum(node.sourceLinks, weightedTarget) / d3.sum(node.sourceLinks, value);
            node.y += (y - center(node)) * alpha;
          }
        });
      });

      function weightedTarget(link) {
        return center(link.target) * link.value;
      }
    }

    function resolveCollisions() {
      nodesByBreadth.forEach(function(nodes) {
        var node,
            dy,
            y0 = 0,
            n = nodes.length,
            i;

        // Push any overlapping nodes down.
        nodes.sort(ascendingDepth);
        for (i = 0; i < n; ++i) {
          node = nodes[i];
          dy = y0 - node.y;
          if (dy > 0) node.y += dy;
          y0 = node.y + node.dy + nodePadding;
        }

        // If the bottommost node goes outside the bounds, push it back up.
        dy = y0 - nodePadding - size[1];
        if (dy > 0) {
          y0 = node.y -= dy;

          // Push any overlapping nodes back up.
          for (i = n - 2; i >= 0; --i) {
            node = nodes[i];
            dy = node.y + node.dy + nodePadding - y0;
            if (dy > 0) node.y -= dy;
            y0 = node.y;
          }
        }
      });
    }

    function ascendingDepth(a, b) {
      return a.y - b.y;
    }
  }

  function computeLinkDepths() {
    nodes.forEach(function(node) {
      node.sourceLinks.sort(ascendingTargetDepth);
      node.targetLinks.sort(ascendingSourceDepth);
    });
    nodes.forEach(function(node) {
      var sy = 0, ty = 0;
      node.sourceLinks.forEach(function(link) {
        link.sy = sy;
        sy += link.dy;
      });
      node.targetLinks.forEach(function(link) {
        link.ty = ty;
        ty += link.dy;
      });
    });

    function ascendingSourceDepth(a, b) {
      return a.source.y - b.source.y;
    }

    function ascendingTargetDepth(a, b) {
      return a.target.y - b.target.y;
    }
  }

  function center(node) {
    return node.y + node.dy / 2;
  }

  function value(link) {
    return link.value;
  }

  return sankey;
};

代码运行良好，但我不想使用节点的索引来创建链接。我想使用节点的名称而不是索引。

有人可以帮助我吗？

Answer 1

查看sankey.js的源代码，它期望它们是索引或节点对象本身。您必须预处理数据才能完成您想要的操作。这是非常微不足道的:

// create hash of nodes
var nodeHash = {};
data.nodes.forEach(function(d){
  nodeHash[d.name] = d;
});
// loop links and swap out string for object
data.links.forEach(function(d){
  d.source = nodeHash[d.source];
  d.target = nodeHash[d.target];
});

完整运行代码:

<!DOCTYPE html>
<html>
<body>
  <script>
  
    function randomWord() {
      var chars = ["apple", "orange", "yellow", "pear", "crayon", "boy", "girl"];
      return chars[Math.floor(Math.random() * chars.length)];
    }

    var data = {
      "nodes": [{
        "name": "apple",
        "id": "environment_score"
      }, {
        "name": "orange",
        "id": "environment_score"
      }, {
        "name": "yellow",
        "id": "environment_score"
      }, {
        "name": "pear",
        "id": "environment_score"
      }, {
        "name": "crayon",
        "id": "environment_score"
      }, {
        "name": "girl",
        "id": "environment_score"
      }, {
        "name": "boy",
        "id": "environment_score"
      }],
      "links": [{
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }, {
        "source": randomWord(),
        "value": 0.00283706180951111,
        "target": randomWord()
      }]
    }
    
    // create hash of nodes
    var nodeHash = {};
    data.nodes.forEach(function(d){
      nodeHash[d.name] = d;
    });
    // loop links and swap out string for object
    data.links.forEach(function(d){
      d.source = nodeHash[d.source];
      d.target = nodeHash[d.target];
    });
    
    console.log(data);
    
  </script>
</body>

</html>