--- trunk/OOPSE/libmdtools/Integrator.cpp	2003/09/17 14:22:15	768
+++ trunk/OOPSE/libmdtools/Integrator.cpp	2003/09/24 19:34:39	784
@@ -25,8 +25,7 @@ template<typename T> Integrator<T>::Integrator(SimInfo
   if (info->the_integrator != NULL){
     delete info->the_integrator;
   }
-  info->the_integrator = this;
-
+  
   nAtoms = info->n_atoms;
 
   // check for constraints
@@ -174,9 +173,18 @@ template<typename T> void Integrator<T>::integrate(voi
   dt = info->dt;
   dt2 = 0.5 * dt;
 
+  readyCheck();
+
   // initialize the forces before the first step
 
   calcForce(1, 1);
+
+  if (nConstrained){
+    preMove();
+    constrainA();
+    calcForce(1, 1);    
+    constrainB();
+  }
   
   if (info->setTemp){
     thermalize();
@@ -192,8 +200,8 @@ template<typename T> void Integrator<T>::integrate(voi
   dumpOut->writeDump(info->getTime());
   statOut->writeStat(info->getTime());
 
-  readyCheck();
 
+
 #ifdef IS_MPI
   strcpy(checkPointMsg, "The integrator is ready to go.");
   MPIcheckPoint();
@@ -290,8 +298,6 @@ template<typename T> void Integrator<T>::moveA(void){
   int i, j;
   DirectionalAtom* dAtom;
   double Tb[3], ji[3];
-  double A[3][3], I[3][3];
-  double angle;
   double vel[3], pos[3], frc[3];
   double mass;
 
@@ -327,34 +333,9 @@ template<typename T> void Integrator<T>::moveA(void){
       for (j = 0; j < 3; j++)
         ji[j] += (dt2 * Tb[j]) * eConvert;
 
-      // use the angular velocities to propagate the rotation matrix a
-      // full time step
-
-      dAtom->getA(A);
-      dAtom->getI(I);
-
-      // rotate about the x-axis      
-      angle = dt2 * ji[0] / I[0][0];
-      this->rotate(1, 2, angle, ji, A); 
-
-      // rotate about the y-axis
-      angle = dt2 * ji[1] / I[1][1];
-      this->rotate(2, 0, angle, ji, A);
-
-      // rotate about the z-axis
-      angle = dt * ji[2] / I[2][2];
-      this->rotate(0, 1, angle, ji, A);
-
-      // rotate about the y-axis
-      angle = dt2 * ji[1] / I[1][1];
-      this->rotate(2, 0, angle, ji, A);
-
-      // rotate about the x-axis
-      angle = dt2 * ji[0] / I[0][0];
-      this->rotate(1, 2, angle, ji, A);
+      this->rotationPropagation( dAtom, ji );
 
       dAtom->setJ(ji);
-      dAtom->setA(A);
     }
   }
 
@@ -666,6 +647,41 @@ template<typename T> void Integrator<T>::constrainB(vo
     painCave.isFatal = 1;
     simError();
   }
+}
+
+template<typename T> void Integrator<T>::rotationPropagation
+( DirectionalAtom* dAtom, double ji[3] ){
+
+  double angle;
+  double A[3][3], I[3][3];
+
+  // use the angular velocities to propagate the rotation matrix a
+  // full time step
+
+  dAtom->getA(A);
+  dAtom->getI(I);
+  
+  // rotate about the x-axis      
+  angle = dt2 * ji[0] / I[0][0];
+  this->rotate( 1, 2, angle, ji, A ); 
+  
+  // rotate about the y-axis
+  angle = dt2 * ji[1] / I[1][1];
+  this->rotate( 2, 0, angle, ji, A );
+  
+  // rotate about the z-axis
+  angle = dt * ji[2] / I[2][2];
+  this->rotate( 0, 1, angle, ji, A);
+  
+  // rotate about the y-axis
+  angle = dt2 * ji[1] / I[1][1];
+  this->rotate( 2, 0, angle, ji, A );
+  
+  // rotate about the x-axis
+  angle = dt2 * ji[0] / I[0][0];
+  this->rotate( 1, 2, angle, ji, A );
+  
+  dAtom->setA( A  );    
 }
 
 template<typename T> void Integrator<T>::rotate(int axes1, int axes2,