Link: optimize so that no link {} is used, less than half the ram used

examples/js/src/neighbourSampling-papaparsing/linkForce.js

@@ -8,17 +8,28 @@ function startLinkSimulation() {
   manualStop = true;
   simulation.stop();
   p1 = performance.now();
-  let links = [];
+  let links = [], force;
 
-  // Initialize link array.
-  nodes = simulation.nodes();
-  for (i = nodes.length-1; i >= 1; i--) {
-    for (j = i-1; j >= 0; j--) {
-      links.push({
-        source: nodes[i],
-        target: nodes[j],
-      });
+  if (tweakedVerOfLink) {
+    force = d3.forceLinkTweaked()
+              .distance(function (n) {
+                return distanceFunction(n.source, n.target, props, norm);
+              });
+  }
+  else {
+    for (i = nodes.length-1; i >= 1; i--) {
+      for (j = i-1; j >= 0; j--) {
+        links.push({
+          source: nodes[i],
+          target: nodes[j],
+        });
+      }
     }
+    force = d3.forceLink()
+              .distance(function (n) {
+               return distanceFunction(n.source, n.target, props, norm);
+              })
+             .links(links);
   }
 
   /* Add force
@@ -33,11 +44,6 @@ function startLinkSimulation() {
    * The full pre-calculation will then occur once when the force is being
    *   initialized by the simulation.
    */
-  let force = tweakedVerOfLink ? d3.forceLinkTweaked() : d3.forceLink();
-  force.distance(function (n) {
-         return distanceFunction(n.source, n.target, props, norm);
-        })
-       .links(links);
 
   simulation
     .alphaDecay(0)