fix start of the element (quad)

classic/5.0/src/AbsBeamline/Multipole.cpp

@@ -146,8 +146,8 @@ void Multipole::addKT(int i, double t, Vector_t &K) {
 
 bool Multipole::apply(const size_t &i, const double &t, double E[], double B[]) {
     Vector_t Ev(0, 0, 0), Bv(0, 0, 0);
-
-    const Vector_t Rt(RefPartBunch_m->getX(i) - dx_m, RefPartBunch_m->getY(i) - dy_m , RefPartBunch_m->getZ(i) - startField_m - ds_m);
+    
+    const Vector_t Rt(RefPartBunch_m->getX(i) - dx_m, RefPartBunch_m->getY(i) - dy_m , RefPartBunch_m->getZ(i) - ds_m);
     // before misalignment    Vector_t Rt(RefPartBunch_m->getX(i), RefPartBunch_m->getY(i), RefPartBunch_m->getZ(i));
 
     if(apply(Rt, Vector_t(0.0), t, Ev, Bv)) return true;
@@ -163,8 +163,8 @@ bool Multipole::apply(const size_t &i, const double &t, double E[], double B[])
 }
 
 bool Multipole::apply(const size_t &i, const double &t, Vector_t &E, Vector_t &B) {
-    
-    const Vector_t temp(RefPartBunch_m->getX(i) - dx_m, RefPartBunch_m->getY(i) - dy_m , RefPartBunch_m->getZ(i) - startField_m - ds_m);
+
+    const Vector_t temp(RefPartBunch_m->getX(i) - dx_m, RefPartBunch_m->getY(i) - dy_m , RefPartBunch_m->getZ(i) - ds_m);
     // before misalignment Vector_t temp(RefPartBunch_m->getX(i), RefPartBunch_m->getY(i), RefPartBunch_m->getZ(i));
 
     const Vector_t &R(temp);
@@ -248,7 +248,7 @@ bool Multipole::apply(const Vector_t &R0, const Vector_t &centroid, const double
     const Vector_t R = R0 - Vector_t(dx_m,dy_m,ds_m);
 
    
-   const Vector_t tmpR(R(0) - dx_m, R(1) - dy_m, R(2) - startField_m - ds_m);
+   const Vector_t tmpR(R(0) - dx_m, R(1) - dy_m, R(2) - ds_m);
 
     if(tmpR(2) > startField_m && tmpR(2) <= endField_m) {
         if(max_NormalComponent_m > 0) {