From 07366afcfc68968a1f5dfd55f21426b51efe5aa8 Mon Sep 17 00:00:00 2001
From: Lucas Dohmen <lucas@arangodb.com>
Date: Tue, 26 Jun 2012 15:25:26 +0200
Subject: [PATCH] Added two measurements to graphs

* diameter
* radius
---
 js/common/modules/graph.js                 | 41 ++++++++++++++++++++++
 js/common/tests/shell-graph-measurement.js | 33 +++++++++++++++--
 2 files changed, 72 insertions(+), 2 deletions(-)

diff --git a/js/common/modules/graph.js b/js/common/modules/graph.js
index c54f884034..d4faed0eff 100644
--- a/js/common/modules/graph.js
+++ b/js/common/modules/graph.js
@@ -1493,6 +1493,47 @@ Graph.prototype.size = function () {
   return this._edges.count();
 };
 
+////////////////////////////////////////////////////////////////////////////////
+/// @brief calculate a measurement
+///
+/// @FUN{@FA{vertex}.measurement(@FA{measurement})}
+///
+/// Calculates the eccentricity or closeness of the vertex
+///
+////////////////////////////////////////////////////////////////////////////////
+
+Graph.prototype.measurement = function (measurement) {
+  var graph = this,
+    vertices = graph._vertices.toArray(),
+    start_value;
+
+  switch (measurement) {
+  case "diameter":
+    start_value = 0;
+    break;
+  case "radius":
+    start_value = Infinity;
+    break;
+  default:
+    throw "Unknown Measurement '" + measurement + "'";
+  }
+
+  return vertices.reduce(function (calculated, vertex) {
+    vertex = graph.getVertex(vertex._id);
+
+    switch (measurement) {
+    case "diameter":
+      calculated = Math.max(calculated, vertex.measurement("eccentricity"));
+      break;
+    case "radius":
+      calculated = Math.min(calculated, vertex.measurement("eccentricity"));
+      break;
+    }
+
+    return calculated;
+  }, start_value);
+};
+
 ////////////////////////////////////////////////////////////////////////////////
 /// @}
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/js/common/tests/shell-graph-measurement.js b/js/common/tests/shell-graph-measurement.js
index a2c302b018..529d1659aa 100644
--- a/js/common/tests/shell-graph-measurement.js
+++ b/js/common/tests/shell-graph-measurement.js
@@ -179,14 +179,43 @@ function measurementSuite() {
 /// @brief test to get an unknown measurement for a vertex
 ////////////////////////////////////////////////////////////////////////////////
 
-    testUnknownMeasurement : function () {
+    testUnknownMeasurementOnVertex : function () {
       var v1 = graph.addVertex(1);
 
       assertException(function () {
         v1.measurement("unknown");
       });
-    }
+    },
 
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test to get diameter and radius for a graph
+////////////////////////////////////////////////////////////////////////////////
+
+    testDiameterAndRadius : function () {
+      var v1 = graph.addVertex(1),
+        v2 = graph.addVertex(2),
+        v3 = graph.addVertex(3),
+        v4 = graph.addVertex(4),
+        v5 = graph.addVertex(5);
+
+      graph.addEdge(v1, v2);
+      graph.addEdge(v1, v3);
+      graph.addEdge(v1, v4);
+      graph.addEdge(v4, v5);
+
+      assertEqual(graph.measurement("diameter"), 3);
+      assertEqual(graph.measurement("radius"), 2);
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test to get an unknown measurement for a graph
+////////////////////////////////////////////////////////////////////////////////
+
+    testUnknownMeasurementOnGraph : function () {
+      assertException(function () {
+        graph.measurement("unknown");
+      });
+    }
   };
 }