Refactor DFT+U base: unify DFTU_BASE namespace and slim Plus_U_Base

- Rename dftu_output.{h,cpp} -> dftu_base_io.{h,cpp},
  dftu_tools_pw.{h,cpp} -> dftu_base_tools.{h,cpp},
  dftu_cal_occ_pw.cpp -> dftu_base_occ.cpp (git mv)
- Unify all DFTU-related free functions in module_pwdft under a single
  namespace DFTU_BASE (formerly dftu_io, dftu_pw, and pw::iter_init_dftu_pw)
- Extract read_occup_m and local_occup_bcast from Plus_U_Base as
  DFTU_BASE:: free functions declared in dftu_base_io.h; dependencies
  (occ_mat, orbital_corr, occ_mat_ctrl) are now passed explicitly
- Replace element-wise MPI_Bcast in local_occup_bcast with whole-matrix
  Parallel_Common::bcast_double calls (rule: no direct MPI usage)
- dftu_lcao_test links one extra light source (dftu_base_io.cpp) so that
  the heavy PW implementation dftu_base_occ.cpp stays out of the test
  closure
- Move JacobiRotate/CalculateEigenvalues helpers into an anonymous
  namespace and drop an unused local variable during migration

Verification: full incremental build passes in build/ (abacus_basic_para,
100%); in build_max_para_test/ the targets dftu_lcao_test and
dftu_pw_test build and link successfully (100%); grep confirms no
references remain to dftu_io, dftu_pw::, dftu_output, dftu_tools_pw,
dftu_cal_occ_pw, or the removed Plus_U_Base members.

Author: abacus_fixer

source/Makefile.Objects

@@ -746,9 +746,9 @@ OBJS_SRCPW=h_ewald_pw.o\
     setup_pwwfc.o\
     update_cell_pw.o\
     dftu_base.o\
-    dftu_output.o\
-    dftu_tools_pw.o\
-    dftu_cal_occ_pw.o\
+    dftu_base_io.o\
+    dftu_base_occ.o\
+    dftu_base_tools.o\
     setup_dftu_pw.o\
     deltaspin_pw.o\
     force_pw.o\

source/source_esolver/esolver_ks_pw.cpp

@@ -202,7 +202,7 @@ void ESolver_KS_PW<T, Device>::iter_init(UnitCell& ucell, const int istep, const
 
     // update local occupations for DFT+U
     // should before lambda loop in DeltaSpin
-    pw::iter_init_dftu_pw(iter,
+    DFTU_BASE::iter_init_dftu_pw(iter,
                           istep,
                           this->dftu,
                           this->stp.template get_psi_t<T, Device>(),

source/source_lcao/module_dftu/test/CMakeLists.txt

@@ -4,7 +4,7 @@ AddTest(
   TARGET dftu_pw_test
   LIBS base device parameter
   SOURCES dftu_pw_test.cpp
-                ../../../source_pw/module_pwdft/dftu_tools_pw.cpp
+                ../../../source_pw/module_pwdft/dftu_base_tools.cpp
 )
 
 AddTest(
@@ -25,6 +25,7 @@ AddTest(
   LIBS parameter psi base device container
   SOURCES dftu_lcao_test.cpp ../dftu_lcao_op.cpp ../dftu_fs.cpp
   ../../../source_pw/module_pwdft/dftu_base.cpp
+  ../../../source_pw/module_pwdft/dftu_base_io.cpp
   ../../../source_hamilt/module_hcontainer/func_folding.cpp
   ../../../source_hamilt/module_hcontainer/base_matrix.cpp
   ../../../source_hamilt/module_hcontainer/hcontainer.cpp

source/source_lcao/module_dftu/test/dftu_pw_test.cpp

@@ -5,7 +5,7 @@
 #include "source_io/module_parameter/parameter.h"
 #undef private
 #include "source_base/matrix.h"
-#include "source_pw/module_pwdft/dftu_tools_pw.h"
+#include "source_pw/module_pwdft/dftu_base_tools.h"
 
 /***********************************************************************
  * Unit tests for DFT+U PW nspin=1/2/4 support (PR-2)
@@ -83,7 +83,7 @@ TEST_F(DftuPwTest, PotOnsitePotNspin1_DiagonalLocale)
         occ_mat_c[m * m_size + m] = 0.3; // diagonal
 
     std::vector<std::complex<double>> pot_onsite(size, {0.0, 0.0});
-    dftu_pw::compute_pot_onsite_scalar(pot_onsite.data(), occ_mat_c.data(), U_val, 0.5, 1.0, m_size);
+    DFTU_BASE::compute_pot_onsite_scalar(pot_onsite.data(), occ_mat_c.data(), U_val, 0.5, 1.0, m_size);
 
     // diagonal: U*(0.5 - 0.3) = 4.0*0.2 = 0.8
     for (int m = 0; m < m_size; m++)
@@ -107,8 +107,8 @@ TEST_F(DftuPwTest, PotOnsitePotNspin2_TwoSpinChannels)
 
     std::vector<std::complex<double>> pot_onsite_up(size, {0.0, 0.0});
     std::vector<std::complex<double>> pot_onsite_dn(size, {0.0, 0.0});
-    dftu_pw::compute_pot_onsite_scalar(pot_onsite_up.data(), occ_mat_up.data(), U_val, 0.5, 0.5, m_size);
-    dftu_pw::compute_pot_onsite_scalar(pot_onsite_dn.data(), occ_mat_dn.data(), U_val, 0.5, 0.5, m_size);
+    DFTU_BASE::compute_pot_onsite_scalar(pot_onsite_up.data(), occ_mat_up.data(), U_val, 0.5, 0.5, m_size);
+    DFTU_BASE::compute_pot_onsite_scalar(pot_onsite_dn.data(), occ_mat_dn.data(), U_val, 0.5, 0.5, m_size);
 
     // pot_onsite_up[0,0] = U*(0.5 - 0.4) = 0.5
     EXPECT_DOUBLE_EQ(pot_onsite_up[0].real(), 0.5);
@@ -133,7 +133,7 @@ TEST_F(DftuPwTest, PotOnsitePotNspin4_PauliTransform)
     pot_onsite[2] = {0.3, 0.0}; // sigma_y
     pot_onsite[3] = {0.2, 0.0}; // sigma_z
 
-    dftu_pw::pauli_to_spin_basis(pot_onsite, m_size);
+    DFTU_BASE::pauli_to_spin_basis(pot_onsite, m_size);
 
     EXPECT_DOUBLE_EQ(pot_onsite[0].real(), 0.6);  // 0.5*(1.0+0.2)
     EXPECT_DOUBLE_EQ(pot_onsite[0].imag(), 0.0);
@@ -164,7 +164,7 @@ TEST_F(DftuPwTest, EnergyNspin12_DiagonalLocale)
 
     // nspin=1: E = U * 1.0 * (0.5^2 + 0.3^2 + 0.2^2) = 4 * 0.38 = 1.52
     std::vector<std::complex<double>> pot_onsite_nspin1(size, {0.0, 0.0});
-    double energy_u = dftu_pw::compute_pot_onsite_scalar(
+    double energy_u = DFTU_BASE::compute_pot_onsite_scalar(
         pot_onsite_nspin1.data(), occ_mat_c.data(), U_val, 0.5, 1.0, m_size);
     EXPECT_DOUBLE_EQ(energy_u, 1.52);
 
@@ -174,9 +174,9 @@ TEST_F(DftuPwTest, EnergyNspin12_DiagonalLocale)
     std::vector<std::complex<double>> pot_onsite_up(size, {0.0, 0.0});
     std::vector<std::complex<double>> pot_onsite_dn(size, {0.0, 0.0});
     energy_u = 0.0;
-    energy_u += dftu_pw::compute_pot_onsite_scalar(
+    energy_u += DFTU_BASE::compute_pot_onsite_scalar(
         pot_onsite_up.data(), occ_mat_up.data(), U_val, 0.5, 0.5, m_size);
-    energy_u += dftu_pw::compute_pot_onsite_scalar(
+    energy_u += DFTU_BASE::compute_pot_onsite_scalar(
         pot_onsite_dn.data(), occ_mat_dn.data(), U_val, 0.5, 0.5, m_size);
     // E = U*0.5*(0.4^2 + 0.6^2) = 4*0.5*(0.16+0.36) = 1.04
     EXPECT_DOUBLE_EQ(energy_u, 1.04);
@@ -200,7 +200,7 @@ TEST_F(DftuPwTest, EnergyNspin4_WithOffDiagonal)
     occ_mat_c[size + 2] = 0.0; occ_mat_c[size + 3] = 0.2;
 
     std::vector<std::complex<double>> pot_onsite(size * 4, {0.0, 0.0});
-    double energy_u = dftu_pw::compute_pot_onsite_spinor(
+    double energy_u = DFTU_BASE::compute_pot_onsite_spinor(
         pot_onsite.data(), occ_mat_c.data(), U_val, 1.0, weight_eu, m_size);
 
     // is=0: 2*0.25*(0.5*0.5 + 0.1*0.1 + 0.1*0.1 + 0.5*0.5) = 0.26
@@ -227,7 +227,7 @@ TEST_F(DftuPwTest, LocaleAccumNspin12)
     wg(0, 1) = 0.5;
 
     std::vector<double> occ_mat_c(m_size * m_size, 0.0);
-    dftu_pw::accumulate_occ_scalar(
+    DFTU_BASE::accumulate_occ_scalar(
         occ_mat_c.data(), becp.data(), nbands, nkb,
         begin_ih, m_begin, m_size, wg, ik);
 
@@ -261,7 +261,7 @@ TEST_F(DftuPwTest, LocaleAccumNspin4_PauliComponents)
 
     ModuleBase::matrix wg(1, nbands);
     wg(0, 0) = 1.0;
-    dftu_pw::accumulate_occ_spinor(
+    DFTU_BASE::accumulate_occ_spinor(
         occ_mat_c.data(), becp.data(), nbands, npol, nkb,
         0, 0, m_size, wg, ik);
 

source/source_lcao/setup_dftu_lcao.cpp

@@ -3,7 +3,7 @@
 #include "source_lcao/module_dftu/dftu_lcao_occ.h"
 #include "source_lcao/module_dftu/dftu_lcao_energy.h"
 #include "source_lcao/module_dftu/dftu_yukawa.h"
-#include "source_pw/module_pwdft/dftu_output.h" // mohan add 2025-11-08
+#include "source_pw/module_pwdft/dftu_base_io.h" // mohan add 2025-11-08
 #include "source_estate/module_dm/density_matrix.h"
 #include "source_lcao/hamilt_lcao.h"
 
@@ -73,7 +73,7 @@ void finish_dftu_lcao(const int iter,
         }
         DFTU_LCAO::cal_energy_correction(*dftu_ptr, ucell);
     }
-    dftu_io::output(*dftu_ptr, ucell, out_chg, global_out_dir, nspin, npol);
+    DFTU_BASE::output(*dftu_ptr, ucell, out_chg, global_out_dir, nspin, npol);
 
     /// use the converged occupation matrix for next MD/Relax SCF calculation
     if (conv_esolver)

source/source_pw/module_pwdft/CMakeLists.txt

@@ -13,9 +13,9 @@ list(APPEND objects
     op_pw_exx_ace.cpp
     op_pw_exx_pot.cpp
     dftu_base.cpp
-    dftu_output.cpp
-    dftu_tools_pw.cpp
-    dftu_cal_occ_pw.cpp
+    dftu_base_io.cpp
+    dftu_base_occ.cpp
+    dftu_base_tools.cpp
     setup_pot.cpp
     setup_pwrho.cpp
     setup_pwwfc.cpp