feat(ui): add type filter toggles

node_modules/dagre/lib/order/cross-count.js

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+"use strict";
+
+var _ = require("../lodash");
+
+module.exports = crossCount;
+
+/*
+ * A function that takes a layering (an array of layers, each with an array of
+ * ordererd nodes) and a graph and returns a weighted crossing count.
+ *
+ * Pre-conditions:
+ *
+ *    1. Input graph must be simple (not a multigraph), directed, and include
+ *       only simple edges.
+ *    2. Edges in the input graph must have assigned weights.
+ *
+ * Post-conditions:
+ *
+ *    1. The graph and layering matrix are left unchanged.
+ *
+ * This algorithm is derived from Barth, et al., "Bilayer Cross Counting."
+ */
+function crossCount(g, layering) {
+  var cc = 0;
+  for (var i = 1; i < layering.length; ++i) {
+    cc += twoLayerCrossCount(g, layering[i-1], layering[i]);
+  }
+  return cc;
+}
+
+function twoLayerCrossCount(g, northLayer, southLayer) {
+  // Sort all of the edges between the north and south layers by their position
+  // in the north layer and then the south. Map these edges to the position of
+  // their head in the south layer.
+  var southPos = _.zipObject(southLayer,
+    _.map(southLayer, function (v, i) { return i; }));
+  var southEntries = _.flatten(_.map(northLayer, function(v) {
+    return _.sortBy(_.map(g.outEdges(v), function(e) {
+      return { pos: southPos[e.w], weight: g.edge(e).weight };
+    }), "pos");
+  }), true);
+
+  // Build the accumulator tree
+  var firstIndex = 1;
+  while (firstIndex < southLayer.length) firstIndex <<= 1;
+  var treeSize = 2 * firstIndex - 1;
+  firstIndex -= 1;
+  var tree = _.map(new Array(treeSize), function() { return 0; });
+
+  // Calculate the weighted crossings
+  var cc = 0;
+  _.forEach(southEntries.forEach(function(entry) {
+    var index = entry.pos + firstIndex;
+    tree[index] += entry.weight;
+    var weightSum = 0;
+    while (index > 0) {
+      if (index % 2) {
+        weightSum += tree[index + 1];
+      }
+      index = (index - 1) >> 1;
+      tree[index] += entry.weight;
+    }
+    cc += entry.weight * weightSum;
+  }));
+
+  return cc;
+}