X-Git-Url: http://git.treefish.org/~alex/phys/u1casc.git/blobdiff_plain/122860ecfb20eedd86f4e9c674f7afa21099caa2..65fa392bb1e02b52b05bea7b7c10efc6f421830a:/u1casc-ordinary/obs_plaq.hpp?ds=sidebyside

diff --git a/u1casc-ordinary/obs_plaq.hpp b/u1casc-ordinary/obs_plaq.hpp
index 5dacf68..63e5296 100644
--- a/u1casc-ordinary/obs_plaq.hpp
+++ b/u1casc-ordinary/obs_plaq.hpp
@@ -27,7 +27,9 @@ private:
   obsmem* OM;
 
   void plaqCompute();
-  static double plaqSus(vector< vector<double> > *vals, void *para);
+
+  static void prePlaqSus(vector< vector <double> > *allVals, vector <double> *preCalculated, void *para);
+  static double plaqSus(vector <double> *preCalculated, vector<double> *excludedMeas, int nmeas, void *para);
 
   sim *Sim;
   obstat<double,double> oPlaq;
@@ -57,7 +59,7 @@ void obs_plaq::_finish() {
   int compid_plaq, compid_plaqsus;
 
   compid_plaq = oPlaq.computeEasy();
-  compid_plaqsus = oPlaq.computeJack(obs_plaq::plaqSus, &(Sim->lsize4));
+  compid_plaqsus = oPlaq.computeJack(obs_plaq::prePlaqSus, obs_plaq::plaqSus, &(Sim->lsize4));
 
   *out << "\t" << oPlaq.getMean(compid_plaq) << "\t" << oPlaq.getErr(compid_plaq);
   *out << "\t" << oPlaq.getMean(compid_plaqsus) << "\t" << oPlaq.getErr(compid_plaqsus);
@@ -81,17 +83,20 @@ void obs_plaq::plaqCompute()
   OM->plaq /= Sim->lsize4*6;
 }
 
-double obs_plaq::plaqSus(vector< vector<double> > *vals, void *para) {
-  double mean=0, mean2=0;
-  for(vector< vector<double> >::iterator valIt = vals->begin(); valIt != vals->end(); ++valIt)  
-    {
-      mean += (*valIt)[0];
-      mean2 += pow((*valIt)[0],2);
-    }
-  mean /= vals->size();
-  mean2 /= vals->size();
-  
-  return ( mean2 - pow(mean,2) ) * *(int*)para * 6;
+void obs_plaq::prePlaqSus(vector< vector <double> > *allVals, vector <double> *preCalculated, void *para) {
+  preCalculated->push_back(0);
+  preCalculated->push_back(0);
+
+  for(vector< vector<double> >::iterator valIt = allVals->begin(); valIt != allVals->end(); ++valIt) {
+    (*preCalculated)[0] += (*valIt)[0];
+    (*preCalculated)[1] += pow((*valIt)[0],2);
+  }
+}
+
+double obs_plaq::plaqSus(vector <double> *preCalculated, vector<double> *excludedMeas, int nmeas, void *para) {
+  return (( (*preCalculated)[1] - pow((*excludedMeas)[0], 2) ) / (nmeas-1)
+	  - pow( ( (*preCalculated)[0] - (*excludedMeas)[0] ) / (nmeas-1), 2 ))
+    * *(int*)para * 6;
 }
 
 #endif