TUNE TPS2; c) Don't recompute LHS from A and Q

+ already done within self._StepPrepareWithoutTaskManager()

integrators/tps2.py

@@ -219,25 +219,22 @@ class TPS2(_tpsx.TPSX, \
       or self.parameters.maxwellCoupling == "strayField" ):
       self._Mag.v.hs.SetZero()
     
-    # assemble blf and lf
-    A = self._A_stat + self._A_instat
-    
     itnr = 0 
     oldIterate = np.array( self._Mag.v.gf.vec.FV() )
     
     diff_gf = GridFunction(self._X)
     diff_cf = diff_gf
     
+    # assemble blf and lf
     self._Assemble_f_fix()
 
     for itnr in range(self._maxiter):
       self._Assemble_f_iter()
       f = self._f_fix.vec.FV().NumPy() + self._f_iter.vec.FV().NumPy()
 
-      LHS = self._Q.dot( A.dot( self._Q.transpose() ) ) 
       RHS = self._Q.dot( f )
     
-      w, succ = scipy.sparse.linalg.gmres(LHS, RHS , x0=None \
+      w, succ = scipy.sparse.linalg.gmres(self._LHS, RHS , x0=None \
         , tol=self._solvetol, maxiter=4000, M=None)
       self._Mag.v.gf.vec.FV().NumPy()[:] = self._Q.transpose().dot(w)