Fixed A* and removed front() method from priority queue

node/PublicResources/js/aStar.js

@@ -1,6 +1,8 @@
 import { PriorityQueue } from "../js/queue.js";
 import { heuristicApprox } from "../js/pathModules.js";
 
+export { aStar };
+
 /**
  * This functions changes the network elements. The nodes have their distanceOrigin
  * property and their parent property assigned. This allows for the traceback
@@ -13,7 +15,7 @@ import { heuristicApprox } from "../js/pathModules.js";
  */
 function aStar(cyGraph, startNode, endNode) {
   let pending = new PriorityQueue(); // Open list
-  let fullyExpanded = new Set(); // Close list
+  let fullyExpanded = new Set(); // Closed list
   let currentShortest = {}; // The minimum distance element from the priority queue.
 
   // Initialization
@@ -53,6 +55,7 @@ function aStar(cyGraph, startNode, endNode) {
             if (successor.data("distanceOrigin") <= possibleImprovedCost) {
               return;
             }
+            pending.nodes.splice(pending.nodes.indexOf(successor), 1);
           }
           // If the successor is in the closed list, but possibly needs reassessment:
           else if (fullyExpanded.has(successor)) {
@@ -69,8 +72,8 @@ function aStar(cyGraph, startNode, endNode) {
             possibleImprovedCost +
               heuristicApprox(cyGraph, successor.id(), endNode.id())
           );
-          pending.enqueue(successor);
           successor.data("_parent", currentShortest.id());
+          pending.enqueue(successor);
         }
       }
     });
@@ -85,5 +88,3 @@ function aStar(cyGraph, startNode, endNode) {
     );
   }
 }
-
-export { aStar };

node/PublicResources/js/dijkstra.js

@@ -1,6 +1,8 @@
 import { PriorityQueue } from "../js/queue.js";
 import { initializeSingleSource, relax } from "../js/pathModules.js";
 
+export { dijkstra };
+
 /**
  * Dijkstra's algorithm will find the shortest path between all nodes in a weighted graph.
  * @param {Class} cyGraph The graph nodes will be updated with new distances
@@ -12,14 +14,13 @@ function dijkstra(cyGraph, startNode) {
   initializeSingleSource(graph, startNode);
   let queue = new PriorityQueue();
 
-  // Initialization
   queue.enqueue(startNode);
 
   while (!queue.isEmpty()) {
     let shortestDistance = queue.dequeue();
     let nodes = shortestDistance.openNeighborhood((ele) => ele.isNode());
 
-    // For loop that checks if node can traverse each edge
+    // For loop that relaxes each successor of the shortestDistance node
     for (let i = 0; i < nodes.length; i++) {
       let edge = graph.getElementById(
         `${shortestDistance.id()}${nodes[i].id()}`
@@ -32,5 +33,3 @@ function dijkstra(cyGraph, startNode) {
     }
   }
 }
-
-export { dijkstra };

node/PublicResources/js/queue.js

@@ -44,16 +44,6 @@ class PriorityQueue {
     }
   }
 
-  front() {
-    if (this.isEmpty()) {
-      throw new Error("There is no front. The queue is empty!");
-    }
-    // Return the lowest distance element, as this is a minimum priority queue.
-    else {
-      return this.nodes[0];
-    }
-  }
-
   isEmpty() {
     return this.nodes.length === 0;
   }