[Positioning] Stock::closest_calibration_request()

Add CalibrationRequest Stock::closest_calibration_request(Request).

owlps-positioning/src/stock.cc

@@ -256,8 +256,9 @@ const ReferencePoint& Stock::
 closest_reference_point(const Request &request)
 {
   if (reference_points.empty())
-    throw element_not_found("Cannot search for the closest reference \
-point: reference point list is empty!") ;
+    throw element_not_found(
+      "Cannot search for the closest reference point: reference points'"
+      " list is empty!") ;
 
   unordered_set<ReferencePoint>::const_iterator i =
     reference_points.begin() ;
@@ -289,3 +290,30 @@ find_create_calibration_request(const CalibrationRequest &request)
     calibration_requests.insert(request) ;
   return *ret.first ;
 }
+
+
+const CalibrationRequest& Stock::
+closest_calibration_request(const Request &request)
+{
+  if (calibration_requests.empty())
+    throw element_not_found(
+      "Cannot search for the closest calibration request: calibration"
+      " requests' list is empty!") ;
+
+  unordered_set<CalibrationRequest>::const_iterator i =
+    calibration_requests.begin() ;
+  float distance = i->ss_square_distance(request) ;
+  unordered_set<CalibrationRequest>::const_iterator closest = i ;
+
+  for (++i ; i != calibration_requests.end() ; ++i)
+    {
+      float tmp_distance = i->ss_square_distance(request) ;
+      if (tmp_distance < distance)
+        {
+          distance = tmp_distance ;
+          closest = i ;
+        }
+    }
+
+  return *closest ;
+}

owlps-positioning/src/stock.hh

@@ -101,6 +101,10 @@ public:
   /// Search for a CalibrationRequest and add it if it does not exist
   static const CalibrationRequest&
   find_create_calibration_request(const CalibrationRequest &request) ;
+  /// \brief Search for the closest CalibrationRequest (in the signal
+  /// strength space) to a given Request
+  static const CalibrationRequest&
+  closest_calibration_request(const Request &request) ;
   //@}
 
   /// Deletes all elements in all attributes