Refactor: eliminate most use of LOWF instance in esolver - step 1 (#…

…4273)

* begin

* add some new functions

* change some function names and add more annotations

* remove the use of paraV in most part of esolver

* correct the caplitalization of orb_con.ParaV

* remove the read-in of lowf file temporarily

* correct the use of orb_con in esolver_ks_lcao_elec

* correct for exx

source/module_elecstate/elecstate_lcao.h

@@ -16,13 +16,23 @@ class ElecStateLCAO : public ElecState
 {
   public:
     ElecStateLCAO(){} // will be called by ElecStateLCAO_TDDFT
+    /*
+    Note: on the removal of LOWF
+    The entire instance of Local_Orbital_wfc is not really necessary, because
+    this class only need it to do 2dbcd wavefunction gathering. Therefore, 
+    what is critical is the 2dbcd handle which stores information about the
+    wavefunction, and another free function to do the 2dbcd gathering.
+
+    A future work would be replace the Local_Orbital_wfc with a 2dbcd handle.
+    A free gathering function will also be needed.
+    */
     ElecStateLCAO(Charge* chg_in ,
                   const K_Vectors* klist_in ,
                   int nks_in,
                   Local_Orbital_Charge* loc_in ,
                   Gint_Gamma* gint_gamma_in,  //mohan add 2024-04-01
                   Gint_k* gint_k_in, //mohan add 2024-04-01
-                  Local_Orbital_wfc* lowf_in ,
+                  Local_Orbital_wfc* lowf_in,
                   ModulePW::PW_Basis* rhopw_in ,
                   ModulePW::PW_Basis_Big* bigpw_in )
     {

source/module_elecstate/elecstate_lcao_tddft.cpp

@@ -51,7 +51,6 @@ void ElecStateLCAO_TDDFT::psiToRho_td(const psi::Psi<std::complex<double>>& psi)
         }
     }
 
-    //this->loc->cal_dk_k(*this->lowf->gridt, this->wg, *(this->klist));
     for (int is = 0; is < GlobalV::NSPIN; is++)
     {
         ModuleBase::GlobalFunc::ZEROS(this->charge->rho[is], this->charge->nrxx); // mohan 2009-11-10

source/module_esolver/esolver_ks_lcao.cpp

@@ -163,10 +163,26 @@ void ESolver_KS_LCAO<TK, TR>::before_all_runners(Input& inp, UnitCell& ucell)
     this->gen_h.LM = &this->LM;
 
     //! pass basis-pointer to EState and Psi
-    this->LOC.ParaV = this->LOWF.ParaV = this->LM.ParaV = &(this->orb_con.ParaV);
+    /*
+    Inform: on getting rid of ORB_control and Parallel_Orbitals
+
+    Have to say it is all the stories start, the ORB_control instance pass its Parallel_Orbitals instance to
+    Local_Orbital_Charge, Local_Orbital_Wfc and LCAO_Matrix, which is actually for getting information
+    of 2D block-cyclic distribution.
+
+    To remove LOC, LOWF and LM use in functions, one must make sure there is no more information imported
+    to those classes. Then places where to get information from them can be substituted to orb_con
+    
+    Plan:
+    1. Specifically for paraV, the thing to do first is to replace the use of ParaV to the oen of ORB_control.
+    Then remove ORB_control and place paraV somewhere.
+    */
+    this->LOC.ParaV = &(this->orb_con.ParaV);
+    this->LOWF.ParaV = &(this->orb_con.ParaV);
+    this->LM.ParaV = &(this->orb_con.ParaV);
 
     // 5) initialize Density Matrix
-    dynamic_cast<elecstate::ElecStateLCAO<TK>*>(this->pelec)->init_DM(&this->kv, this->LM.ParaV, GlobalV::NSPIN);
+    dynamic_cast<elecstate::ElecStateLCAO<TK>*>(this->pelec)->init_DM(&this->kv, &(this->orb_con.ParaV), GlobalV::NSPIN);
 
 
     if (GlobalV::CALCULATION == "get_S")
@@ -232,7 +248,7 @@ void ESolver_KS_LCAO<TK, TR>::before_all_runners(Input& inp, UnitCell& ucell)
     // 10) init HSolver
     if (this->phsol == nullptr)
     {
-        this->phsol = new hsolver::HSolverLCAO<TK>(this->LOWF.ParaV);
+        this->phsol = new hsolver::HSolverLCAO<TK>(&(this->orb_con.ParaV));
         this->phsol->method = GlobalV::KS_SOLVER;
     }
 
@@ -286,7 +302,14 @@ void ESolver_KS_LCAO<TK, TR>::init_after_vc(Input& inp, UnitCell& ucell)
     ModuleBase::timer::tick("ESolver_KS_LCAO", "init_after_vc");
 
 	ESolver_KS<TK>::init_after_vc(inp, ucell);
-
+    /*
+    Notes: on the removal of LOWF
+    Following constructor of ElecStateLCAO requires LOWF. However, ElecState only need
+    LOWF to do wavefunction 2dbcd (2D BlockCyclicDistribution) gathering. So, a free
+    function is needed to replace the use of LOWF. The function indeed needs the information
+    about 2dbcd, therefore another instance storing the information is needed instead.
+    Then that instance will be the input of "the free function to gather".
+    */
     if (GlobalV::md_prec_level == 2)
 	{
 		delete this->pelec;
@@ -296,7 +319,7 @@ void ESolver_KS_LCAO<TK, TR>::init_after_vc(Input& inp, UnitCell& ucell)
 				&(this->LOC),
                 &(this->GG), // mohan add 2024-04-01
                 &(this->GK), // mohan add 2024-04-01
-				&(this->LOWF),
+				&(this->LOWF), // should be replaced by a 2dbcd handle, if insist the "print_psi" must be in ElecState class
 				this->pw_rho,
 				this->pw_big);
 
@@ -657,10 +680,10 @@ void ESolver_KS_LCAO<TK, TR>::iter_init(const int istep, const int iter)
     // first need to calculate the weight according to
     // electrons number.
     if (istep == 0 
-        && this->wf.init_wfc == "file" 
-        && this->LOWF.error == 0)
-    {
-        if (iter == 1)
+        && this->wf.init_wfc == "file" // Note: on the removal of LOWF
+        && this->LOWF.error == 0)      // this means the wavefunction is read without any error.
+    {                                  // However the I/O of wavefunction are nonsence to be implmented in different places.
+        if (iter == 1)                 // once the reading of wavefunction has any error, should exit immediately.
         {
             std::cout << " WAVEFUN -> CHARGE " << std::endl;
 
@@ -831,11 +854,11 @@ void ESolver_KS_LCAO<TK, TR>::hamilt2density(int istep, int iter, double ethr)
 #ifdef __EXX
     if (GlobalC::exx_info.info_ri.real_number)
     {
-        this->exd->exx_hamilt2density(*this->pelec, *this->LOWF.ParaV, iter);
+        this->exd->exx_hamilt2density(*this->pelec, this->orb_con.ParaV, iter);
     }
     else
     {
-        this->exc->exx_hamilt2density(*this->pelec, *this->LOWF.ParaV, iter);
+        this->exc->exx_hamilt2density(*this->pelec, this->orb_con.ParaV, iter);
     }
 #endif
 
@@ -861,8 +884,6 @@ void ESolver_KS_LCAO<TK, TR>::hamilt2density(int istep, int iter, double ethr)
 #ifdef __DEEPKS
     if (GlobalV::deepks_scf)
     {
-        const Parallel_Orbitals* pv = this->LOWF.ParaV;
-
         const std::vector<std::vector<TK>>& dm = 
         dynamic_cast<const elecstate::ElecStateLCAO<TK>*>(this->pelec)->get_DM()->get_DMK_vector();
 
@@ -940,7 +961,7 @@ void ESolver_KS_LCAO<TK, TR>::update_pot(const int istep, const int iter)
                                        GlobalV::out_app_flag, 
                                        "H", 
                                        "data-" + std::to_string(ik), 
-                                       *this->LOWF.ParaV, 
+                                       this->orb_con.ParaV, 
                                        GlobalV::DRANK);
                     ModuleIO::save_mat(istep, 
                                        s_mat.p, 
@@ -951,7 +972,7 @@ void ESolver_KS_LCAO<TK, TR>::update_pot(const int istep, const int iter)
                                        GlobalV::out_app_flag, 
                                        "S", 
                                        "data-" + std::to_string(ik), 
-                                       *this->LOWF.ParaV, 
+                                       this->orb_con.ParaV, 
                                        GlobalV::DRANK);
                 }
             }
@@ -1048,16 +1069,16 @@ void ESolver_KS_LCAO<TK, TR>::iter_finish(int iter)
     if (GlobalC::restart.info_save.save_H && two_level_step > 0 &&
         (!GlobalC::exx_info.info_global.separate_loop || iter == 1)) // to avoid saving the same value repeatedly
     {
-        std::vector<TK> Hexxk_save(this->LOWF.ParaV->get_local_size());
-        for (int ik = 0;ik < this->kv.get_nks();++ik)
+        std::vector<TK> Hexxk_save(this->orb_con.ParaV.get_local_size());
+        for (int ik = 0; ik < this->kv.get_nks(); ++ik)
         {
             ModuleBase::GlobalFunc::ZEROS(Hexxk_save.data(), Hexxk_save.size());
 
             hamilt::OperatorEXX<hamilt::OperatorLCAO<TK, TR>> opexx_save(&this->LM, nullptr, &Hexxk_save, this->kv);
 
             opexx_save.contributeHk(ik);
 
-            GlobalC::restart.save_disk("Hexx", ik, this->LOWF.ParaV->get_local_size(), Hexxk_save.data());
+            GlobalC::restart.save_disk("Hexx", ik, this->orb_con.ParaV.get_local_size(), Hexxk_save.data());
         }
 		if (GlobalV::MY_RANK == 0)
 		{
@@ -1234,7 +1255,7 @@ void ESolver_KS_LCAO<TK, TR>::after_scf(const int istep)
             GlobalC::ucell,
             GlobalC::ORB,
             GlobalC::GridD,
-            this->LOWF.ParaV,
+            &(this->orb_con.ParaV),
             *(this->psi),
             dynamic_cast<const elecstate::ElecStateLCAO<TK>*>(this->pelec)->get_DM());
 
@@ -1251,7 +1272,7 @@ void ESolver_KS_LCAO<TK, TR>::after_scf(const int istep)
         RPA_LRI<TK, double> rpa_lri_double(GlobalC::exx_info.info_ri);
         rpa_lri_double.cal_postSCF_exx(*dynamic_cast<const elecstate::ElecStateLCAO<TK>*>(this->pelec)->get_DM(), MPI_COMM_WORLD, this->kv);
         rpa_lri_double.init(MPI_COMM_WORLD, this->kv);
-        rpa_lri_double.out_for_RPA(*(this->LOWF.ParaV), *(this->psi), this->pelec);
+        rpa_lri_double.out_for_RPA(this->orb_con.ParaV, *(this->psi), this->pelec);
     }
 #endif
 
@@ -1418,7 +1439,7 @@ ModuleIO::Output_Mat_Sparse<TK> ESolver_KS_LCAO<TK, TR>::create_Output_Mat_Spars
 			INPUT.out_mat_r,
 			istep,
 			this->pelec->pot->get_effective_v(),
-			*this->LOWF.ParaV,
+			this->orb_con.ParaV,
             this->gen_h, // mohan add 2024-04-06
             this->GK, // mohan add 2024-04-01
 			this->LM,

source/module_esolver/esolver_ks_lcao_elec.cpp

@@ -109,23 +109,23 @@ void ESolver_KS_LCAO<TK, TR>::beforesolver(const int istep)
         if (GlobalV::GAMMA_ONLY_LOCAL)
         {
             nsk = GlobalV::NSPIN;
-            ncol = this->LOWF.ParaV->ncol_bands;
+            ncol = this->orb_con.ParaV.ncol_bands;
             if (GlobalV::KS_SOLVER == "genelpa" || GlobalV::KS_SOLVER == "lapack_gvx" || GlobalV::KS_SOLVER == "pexsi"
                 || GlobalV::KS_SOLVER == "cusolver")
             {
-                ncol = this->LOWF.ParaV->ncol;
+                ncol = this->orb_con.ParaV.ncol;
             }
         }
         else
         {
             nsk = this->kv.get_nks();
 #ifdef __MPI
-            ncol = this->LOWF.ParaV->ncol_bands;
+            ncol = this->orb_con.ParaV.ncol_bands;
 #else
             ncol = GlobalV::NBANDS;
 #endif
         }
-        this->psi = new psi::Psi<TK>(nsk, ncol, this->LOWF.ParaV->nrow, nullptr);
+        this->psi = new psi::Psi<TK>(nsk, ncol, this->orb_con.ParaV.nrow, nullptr);
     }
 
     // prepare grid in Gint
@@ -504,7 +504,6 @@ void ESolver_KS_LCAO<TK, TR>::nscf(void)
     // Peize Lin add 2018-08-14
     if (GlobalC::exx_info.info_global.cal_exx)
     {
-        // GlobalC::exx_lcao.cal_exx_elec_nscf(this->LOWF.ParaV[0]);
         const std::string file_name_exx = GlobalV::global_out_dir + "HexxR" + std::to_string(GlobalV::MY_RANK);
         if (GlobalC::exx_info.info_ri.real_number)
         {
@@ -600,7 +599,7 @@ void ESolver_KS_LCAO<TK, TR>::nscf(void)
                                 this->sf,
                                 this->kv,
                                 this->psi,
-                                this->LOWF.ParaV);
+                                &(this->orb_con.ParaV));
         }
         else if (INPUT.wannier_method == 2)
         {
@@ -612,7 +611,7 @@ void ESolver_KS_LCAO<TK, TR>::nscf(void)
                                        INPUT.nnkpfile,
                                        INPUT.wannier_spin);
 
-            myWannier.calculate(this->pelec->ekb, this->kv, *(this->psi), this->LOWF.ParaV);
+            myWannier.calculate(this->pelec->ekb, this->kv, *(this->psi), &(this->orb_con.ParaV));
         }
 #endif
     }
@@ -626,7 +625,6 @@ void ESolver_KS_LCAO<TK, TR>::nscf(void)
 
     // below is for DeePKS NSCF calculation
 #ifdef __DEEPKS
-    const Parallel_Orbitals* pv = this->LOWF.ParaV;
     if (GlobalV::deepks_out_labels || GlobalV::deepks_scf)
     {
         const elecstate::DensityMatrix<TK, double>* dm

source/module_esolver/esolver_ks_lcao_tddft.cpp

@@ -102,7 +102,8 @@ void ESolver_KS_LCAO_TDDFT::before_all_runners(Input& inp, UnitCell& ucell)
     // pass Hamilt-pointer to Operator
     this->gen_h.LM = &this->LM;
     // pass basis-pointer to EState and Psi
-    this->LOC.ParaV = this->LOWF.ParaV = this->LM.ParaV;
+    this->LOC.ParaV = this->LM.ParaV;;
+    this->LOWF.ParaV = this->LM.ParaV;
 
     // init DensityMatrix
     dynamic_cast<elecstate::ElecStateLCAO<std::complex<double>>*>(this->pelec)
@@ -111,7 +112,7 @@ void ESolver_KS_LCAO_TDDFT::before_all_runners(Input& inp, UnitCell& ucell)
     // init Psi, HSolver, ElecState, Hamilt
     if (this->phsol == nullptr)
     {
-        this->phsol = new hsolver::HSolverLCAO<std::complex<double>>(this->LOWF.ParaV);
+        this->phsol = new hsolver::HSolverLCAO<std::complex<double>>(this->LM.ParaV);
         this->phsol->method = GlobalV::KS_SOLVER;
     }
 
@@ -274,7 +275,7 @@ void ESolver_KS_LCAO_TDDFT::update_pot(const int istep, const int iter)
                                        GlobalV::out_app_flag,
                                        "H",
                                        "data-" + std::to_string(ik),
-                                       *this->LOWF.ParaV,
+                                       *this->LM.ParaV,
                                        GlobalV::DRANK);
 
                     ModuleIO::save_mat(istep,
@@ -286,7 +287,7 @@ void ESolver_KS_LCAO_TDDFT::update_pot(const int istep, const int iter)
                                        GlobalV::out_app_flag,
                                        "S",
                                        "data-" + std::to_string(ik),
-                                       *this->LOWF.ParaV,
+                                       *this->LM.ParaV,
                                        GlobalV::DRANK);
                 }
             }
@@ -333,8 +334,8 @@ void ESolver_KS_LCAO_TDDFT::update_pot(const int istep, const int iter)
         {
 #ifdef __MPI
             this->psi_laststep = new psi::Psi<std::complex<double>>(kv.get_nks(),
-                                                                    this->LOWF.ParaV->ncol_bands,
-                                                                    this->LOWF.ParaV->nrow,
+                                                                    this->LM.ParaV->ncol_bands,
+                                                                    this->LM.ParaV->nrow,
                                                                     nullptr);
 #else
             this->psi_laststep = new psi::Psi<std::complex<double>>(kv.get_nks(), GlobalV::NBANDS, GlobalV::NLOCAL, nullptr);

source/module_esolver/io_npz.cpp

@@ -33,7 +33,7 @@ void ESolver_KS_LCAO<TK, TR>::read_mat_npz(std::string& zipname, hamilt::HContai
 {
     ModuleBase::TITLE("LCAO_Hamilt","read_mat_npz");
 
-    const Parallel_Orbitals* paraV = this->LOWF.ParaV;
+    const Parallel_Orbitals* paraV = &(this->orb_con.ParaV);
 
 #ifdef __USECNPY
 

source/module_hamilt_lcao/hamilt_lcaodft/local_orbital_wfc.h

@@ -12,9 +12,20 @@ class Local_Orbital_wfc
 {
 public:
 
-	Local_Orbital_wfc();
+	Local_Orbital_wfc();    
 	~Local_Orbital_wfc();
-
+    // refactor new implementation: RAII
+    // a more look-looking name would be LocalOrbitalWfc, I suppose...
+    Local_Orbital_wfc(const int& nspin,
+                      const int& nks,
+                      const int& nbands,
+                      const int& nlocal,
+                      const int& gamma_only,
+                      const int& nb2d,
+                      const std::string& ks_solver,
+                      const std::string& readin_dir);
+    //
+    void initialize();
     ///=========================================
     /// grid wfc
     /// used to generate density matrix: LOC.DM_R,
@@ -25,7 +36,10 @@ class Local_Orbital_wfc
     std::complex<double>*** wfc_k_grid; // [NK, GlobalV::NBANDS, GlobalV::NLOCAL]
     std::complex<double>* wfc_k_grid2;  // [NK*GlobalV::NBANDS*GlobalV::NLOCAL]
 
+    // pointer to const Parallel_Orbitals object
     const Parallel_Orbitals* ParaV;
+    // pointer to const Grid_Technique object, although have no idea about what it is...
+    // the name of Grid_Technique should be changed to be more informative
     const Grid_Technique* gridt;
 
     /// read wavefunction coefficients: LOWF_*.txt
@@ -102,7 +116,7 @@ class Local_Orbital_wfc
     int nks;
 };
 
-#ifdef __MPI
+
 // the function should not be defined here!! mohan 2024-03-28
 template <typename T>
 int Local_Orbital_wfc::set_wfc_grid(int naroc[2],
@@ -116,6 +130,7 @@ int Local_Orbital_wfc::set_wfc_grid(int naroc[2],
                                     int myid,
                                     T** ctot)
 {
+#ifdef __MPI
     ModuleBase::TITLE(" Local_Orbital_wfc", "set_wfc_grid");
     if (!wfc && !ctot)
     {
@@ -142,8 +157,7 @@ int Local_Orbital_wfc::set_wfc_grid(int naroc[2],
 			}
         }
     }
+#endif
     return 0;
 }
 #endif
-
-#endif