Refactor output formats of deltaspin method (deepmodeling#7857)

* deltaspin: mirror print_header output into running_scf.log

Include source_base/global_variable.h in lambda_loop_helper.cpp so the
helper methods can reach GlobalV::ofs_running. For now only print_header
is mirrored; subsequent commits will migrate the remaining helper
functions one at a time so every step builds independently.

stdout is preserved so interactive users and CaptureStdout-based unit
tests (lambda_loop_hlp_test.cpp / deltaspin_core_test.cpp) keep
observing the same terminal output they expect.

* deltaspin: mirror print_termination footer output into running_scf.log

Duplicate the two std::cout lines ("Inner optimization for lambda ends."
and the closing separator) to GlobalV::ofs_running. The internal
print_2d calls are left alone for now; they will be redirected in a
separate commit that touches the shared helper so the change is
centralized.

The unit-test assertions for print_termination in lambda_loop_hlp_test.cpp
are commented out, so there is no test drift to account for in this step.

* deltaspin: mirror check_rms_stop output into running_scf.log

Duplicate Step (Outer -- Inner) RMS/TIME line, both convergence exit
messages, and both cumulative Total TIME lines into
GlobalV::ofs_running alongside the existing std::cout stream.

print_termination() at the exit point already emits duplicates thanks
to the previous commit; no extra forwarding needed here.

CaptureStdout-based tests in lambda_loop_hlp_test.cpp remain valid
because stdout is preserved unmodified.

* deltaspin: mirror check_restriction output into running_scf.log

The two diagnostic lines emitted when the trial step is clipped
("alpha after restrict" and "boundary after") now also land in
running_scf.log. The check_restriction signature stays untouched so
ABACUS rule 5 (no default-argument additions to existing interfaces)
is satisfied and lambda_loop.cpp does not need a call-site update.

* deltaspin: mirror check_gradient_decay diagnostic output to ofs_running

Duplicate the verbose debug block (print=true) and the early-exit
"Reach limitation of current step" message into running_scf.log.

Intentionally not touched in this commit:
  * printf-based [GRAD-DECAY] and [ALPHA-OPT] warnings inside
    check_gradient_decay and cal_alpha_opt — they are only triggered
    under guard conditions that do not fire for the reference
    14_PW_DS_S4_XYZ test case and are addressed separately.
  * The print_2d call in the debug block — that helper has its own
    dedicated redirect commit next.

* deltaspin: mirror print_2d tables into running_scf.log

Include source_base/global_variable.h in basic_funcs.cpp and emit a
duplicate copy of every print_2d line to GlobalV::ofs_running in
addition to the caller-supplied ostream (which defaults to std::cout).

All existing callers benefit from this single change:
  * lambda_loop.cpp    : initial lambda, initial spin, target spin
  * lambda_loop_helper : after-optimization spin/lambda, diagonal
                        gradient diagnostics in check_gradient_decay

Formatting is preserved byte-for-byte by constructing each ATOM line
into a local std::string before streaming to both sinks.
MODULE_LCAO_deltaspin_basic_func_test keeps passing because
stdout still contains the expected output lines.

* deltaspin: mirror run_lambda_loop scalar diagnostics to ofs_running

Include source_base/global_variable.h in lambda_loop.cpp and emit
duplicate copies into running_scf.log for:
  * "Total TIME(s) = ..."  (gradient-decay exit branch)
  * "Current RMS: ..."      (post-inner-loop PW verification)
  * "Error: RMS error is too large, rerun the loop"

The per-step check_rms_stop/print_termination outputs and the
initial lambda/target spin tables already go to both sinks via
earlier commits. No helper signatures changed (ABACUS rule 5
compliance) and no call-site updates are required.

* deltaspin: mirror run_lambda_linear_scan [DS-DIAG] output into running_scf.log

Duplicate every [DS-DIAG] line from run_lambda_linear_scan into
GlobalV::ofs_running alongside std::cout, so the normally-off
diagnostic lambda-scan helper also persists its findings to
running_scf.log.

Scope includes: scan-start banner and parameters, the auto-constrain
notice, per-atom constrain/target dumps, per-step header and Mi
output, consistency-check summary lines, and the completion banner.

Only stdout (default) copies are tested; no unit-test modifications
required because all CaptureStdout expectations remain satisfied.

* elecstate: mirror SCF per-iter compact table to running_scf.log

Append a copy of the per-SCF-iteration summary buffer produced by
print_scf_iterinfo (the line with ITER, TMAGX/TMAGY/TMAGZ/AMAG,
ETOT, EDIFF, DRHO, TIME) to GlobalV::ofs_running so users can get
a compact convergence overview from running_scf.log without having
to scroll back through the interactive terminal output.

The std::flush is preserved on both sinks so large MPI jobs still
see progress line by line during long runs. elecstate already
includes source_base/global_variable.h so no new #include was
necessary.

* deltaspin: split output between screen and running_scf.log

Replace previous dual-write (cout + ofs_running) with strict routing:
information goes to either screen or log, not both.

Screen keeps only:
- SCF iteration compact table (ITER TMAGX ... DRHO TIME/s)
- per-outer-step convergence summary (Meet/Reach criterion, Total TIME)
- error/early-termination notices (Reach limitation, Error: RMS)

Log receives (with leading-space style consistent with running_scf.log):
- per-inner-step Step (Outer -- Inner) RMS = ... TIME(s) = ...
- initial/after-optimization spin and lambda tables (per-atom info kept
  off screen to avoid flooding on large systems)
- alpha after restrict / boundary after diagnostics
- diagonal gradient / maximum gradient appears at / maximum gradient
- Current RMS, Total TIME(s)
- all [DS-DIAG] linear-scan debug lines

print_2d now writes only to the stream passed by caller; no implicit
dual output. Test assertion updated to expect leading space in ATOM rows.

* deltaspin: add RMS column to SCF table, move converged summary to log

Add a new RMS column to the SCF iteration table on screen, placed after
DRHO (and DKIN if present) and before TIME. The column shows the most
recent DeltaSpin lambda-loop RMS in scientific notation. Non-DeltaSpin
calculations do not show this column.

Implementation:
- SpinConstrain: add last_rms_error_ member + get_last_rms_error() getter,
  set in run_lambda_loop when check_rms_stop returns true.
- ESolver_KS: add ds_rms_ member, reset in iter_init to 0.0 when
  sc_mag_switch is on (column shown, value 0 before lambda loop runs)
  or -1.0 otherwise (column hidden).
- ESolver_KS_PW / ESolver_KS_LCAO: after run_lambda_loop, fetch
  sc.get_last_rms_error() into ds_rms_.
- print_etot / print_scf_iterinfo: add ds_rms parameter (default -1.0);
  when >= 0, append an RMS column (same width/format as DRHO) to both
  header and data rows.
- Move the 'DeltaSpin: lambda loop converged' summary line from screen
  to running_scf.log (with leading space and trailing blank line).
  Abnormal summaries (max steps, early-termination, RMS too large)
  remain on screen so users see them immediately.

* deltaspin: remove GlobalV::ofs_running dependency from module_deltaspin

Pass ofs_running explicitly through function parameters instead of
referencing the GlobalV::ofs_running global variable directly inside
the deltaspin module. This follows ABACUS rule deepmodeling#1 (do not increase
cross-layer control through GlobalV) and matches the existing design
pattern used by print_Mi / print_Mag_Force.

Changes:
- spin_constrain.h: add std::ostream& ofs_running parameter to 7
  functions (run_lambda_loop, run_lambda_linear_scan, print_header,
  print_termination, check_rms_stop, check_restriction,
  check_gradient_decay). Added <fstream> include. Removed default
  value for 'rerun' and 'print' parameters to keep call sites
  explicit (rule deepmodeling#5).
- lambda_loop_helper.cpp: replace all GlobalV::ofs_running with the
  ofs_running parameter; remove #include source_base/global_variable.h.
- lambda_loop.cpp: replace all GlobalV::ofs_running with the
  ofs_running parameter; remove #include source_base/global_variable.h
  (kept #include source_io/module_parameter/parameter.h since PARAM is
  still used).
- basic_funcs.cpp: remove unused #include source_base/global_variable.h.
- template_helpers.cpp: update TK=double stub signatures to match.
- deltaspin_lcao.h/cpp: add ofs_running parameter to
  run_deltaspin_lambda_loop_lcao; add <iosfwd> include.
- deltaspin_pw.h/cpp: add ofs_running parameter to
  run_deltaspin_lambda_loop; add <iosfwd> include.
- esolver_ks_pw.cpp / esolver_ks_lcao.cpp: pass GlobalV::ofs_running
  at the call site (the esolver layer owns the dependency).
- template_helpers_test.cpp: pass std::cout at test call sites.

Result: module_deltaspin no longer references GlobalV::ofs_running.
The only remaining GlobalV:: usages in the module are historical MPI
constants (NPROC_IN_POOL, RANK_IN_POOL) in cal_mw*.cpp, untouched by
this change.

* deltaspin: add empty deltaspin_pw_impl.cpp in module_pwdft

Create a placeholder file source/source_pw/module_pwdft/deltaspin_pw_impl.cpp
that will host PW-specific SpinConstrain member function implementations
in subsequent commits:
  - cal_mi_pw()
  - calculate_delta_hcc()
  - update_psi_charge_pw_cpu()
  - update_psi_charge_pw_gpu()

Update source/source_pw/module_pwdft/CMakeLists.txt to include the new
source file in the module_pwdft build list.

The file currently contains only the spinconstrain namespace skeleton
with a comment listing the functions to be moved. No functional change;
the build produces an empty object file.

Verified: make -j 30 in build_max_para_test compiles cleanly and
generates deltaspin_pw_impl.cpp.o.

* deltaspin: move cal_mi_pw implementation to module_pwdft

Relocate the PW-specific SpinConstrain<std::complex<double>>::cal_mi_pw()
member function from module_deltaspin/cal_mw.cpp to
module_pwdft/deltaspin_pw_impl.cpp.

cal_mi_pw() depends on projectors::OnsiteProjector (PW-side atomic
projector) and psi::Psi<complex<double>, DEVICE_CPU/GPU> wavefunction
container, which are PW-specific dependencies that should not be pulled
into module_deltaspin.

Changes:
- module_pwdft/deltaspin_pw_impl.cpp: add cal_mi_pw() implementation
  with required includes (matrix.h, parallel_reduce.h, tool_title.h,
  timer.h, onsite_proj.h, spin_constrain.h, parameter.h).
- module_deltaspin/cal_mw.cpp: remove cal_mi_pw() function body and
  its doxygen comment block; remove now-unused #include
  "source_pw/module_pwdft/onsite_proj.h"; leave a brief comment noting
  the function has been relocated.

The function declaration stays in spin_constrain.h (no interface
change). cal_mi_lcao() and set_operator() remain in cal_mw.cpp.

Verified: make -j 30 in build_max_para_test compiles cleanly.

* deltaspin: move calculate_delta_hcc to module_pwdft

Relocate the PW-specific
SpinConstrain<std::complex<double>>::calculate_delta_hcc() member function
from module_deltaspin/cal_mw_from_lambda.cpp to
module_pwdft/deltaspin_pw_impl.cpp.

calculate_delta_hcc() builds the DeltaSpin correction to the subspace
Hamiltonian (H += becp^d * delta_lambda * becp) using PW projector
coefficients. It is only called by update_psi_charge_pw_cpu/gpu, which
are PW-specific and will be moved in the next step.

Changes:
- module_pwdft/deltaspin_pw_impl.cpp: add calculate_delta_hcc()
  implementation; add #include "source_base/kernels/math_kernel_op.h"
  for ModuleBase::gemm_op used by the function.
- module_deltaspin/cal_mw_from_lambda.cpp: remove calculate_delta_hcc()
  function body and its doxygen comment block; leave a brief comment
  noting the function has been relocated. All call sites within
  update_psi_charge_pw_cpu/gpu (which remain in this file for now)
  continue to work because the function declaration is still in
  spin_constrain.h.

The PW includes (hsolver_pw.h, elecstate_pw.h, onsite_proj.h,
math_kernel_op.h) are still needed by cal_mw_from_lambda.cpp for
update_psi_charge_pw_cpu/gpu; they will be removed in step 4 once
those functions are also relocated.

Verified: make -j 30 in build_max_para_test compiles cleanly.

* deltaspin: move update_psi_charge_pw_cpu/gpu to module_pwdft

Relocate the PW-specific update_psi_charge_pw_cpu() and
update_psi_charge_pw_gpu() member functions from
module_deltaspin/cal_mw_from_lambda.cpp to
module_pwdft/deltaspin_pw_impl.cpp.

These functions depend on PW-specific types:
  - hsolver::HSolverPW (full plane-wave iterative solver)
  - elecstate::ElecStatePW (PW electronic state for psiToRho)
  - projectors::OnsiteProjector (PW atomic projector for becp)
  - hsolver::DiagoIterAssist (subspace diagonalization)

Changes:
- module_pwdft/deltaspin_pw_impl.cpp: add update_psi_charge_pw_cpu()
  and update_psi_charge_pw_gpu() implementations; add includes for
  diago_iter_assist.h, hsolver_pw.h, elecstate_pw.h, elecstate_tools.h.
- module_deltaspin/cal_mw_from_lambda.cpp: remove the two function
  bodies and their doxygen comment blocks; remove now-unused includes
  (hsolver_pw.h, elecstate_pw.h, math_kernel_op.h); remove duplicate
  elecstate_tools.h include; leave a brief comment noting the functions
  have been relocated.

After this change, cal_mw_from_lambda.cpp no longer includes
hsolver_pw.h, elecstate_pw.h, or math_kernel_op.h. The PW-specific
HSolverPW and ElecStatePW dependencies are now fully contained within
module_pwdft.

Note: onsite_proj.h and diago_iter_assist.h are still needed by
cal_mw_from_lambda.cpp because the main cal_mw_from_lambda() function
internally uses OnsiteProjector and DiagoIterAssist for the PW subspace
setup path. These remain as the LCAO/PW dispatch logic in the main
entry point.

The update_psi_charge() dispatch entry and cal_mw_from_lambda() main
function remain in cal_mw_from_lambda.cpp; they call the relocated
PW functions via the class member function declarations in
spin_constrain.h.

Verified: make -j 30 in build_max_para_test compiles cleanly.

* deltaspin: finalize PW code relocation and clean up includes

Clean up unused includes in module_deltaspin/cal_mw.cpp that were left
behind after cal_mi_pw() was moved to module_pwdft in step 2.

Removed includes (verified unused after relocation):
  - <iostream>
  - source_base/matrix.h
  - source_base/name_angular.h
  - source_base/parallel_reduce.h
  - source_io/module_parameter/parameter.h

The remaining includes (tool_title.h, timer.h, spin_constrain.h, and
the __LCAO block) are all still used by cal_mi_lcao() and set_operator().

Final state after the 5-step relocation:
  - module_deltaspin/cal_mw.cpp: only LCAO-specific code
    (cal_mi_lcao, set_operator)
  - module_deltaspin/cal_mw_from_lambda.cpp: main entry points
    (cal_mw_from_lambda, update_psi_charge) + LCAO dispatch;
    no longer includes hsolver_pw.h, elecstate_pw.h, math_kernel_op.h
  - module_pwdft/deltaspin_pw_impl.cpp: all PW-specific implementations
    (cal_mi_pw, calculate_delta_hcc, update_psi_charge_pw_cpu/gpu)
  - module_pwdft/deltaspin_pw.cpp: PW wrapper (unchanged)

Verification:
  - make -j 30 in build_max_para_test compiles cleanly.
  - All 5 deltaspin unit tests pass: MODULE_ESTATE_elecstate_print,
    MODULE_LCAO_deltaspin_basic_func_test,
    MODULE_LCAO_deltaspin_template_helpers, deltaspin_pw_test,
    deltaspin_core_test.
  - grep confirms module_deltaspin/*.cpp no longer include
    hsolver_pw.h, elecstate_pw.h, or math_kernel_op.h.
  - onsite_proj.h is still included by cal_mw_from_lambda.cpp because
    the main cal_mw_from_lambda() function uses OnsiteProjector for the
    PW subspace setup path; this is the LCAO/PW dispatch logic that
    stays in the main entry point.

* deltaspin: lift 6 lambda-loop helpers out of SpinConstrain class

Phase 1 of god-class slimming: lift six lambda-loop helper methods
(check_rms_stop, check_restriction, check_gradient_decay,
cal_alpha_opt, print_header, print_termination) out of the
SpinConstrain<TK> class template and into free function templates
in the spinconstrain namespace.

Motivation
----------
spin_constrain.h is a god class with 7+ mixed responsibilities. The
lambda-loop workflow helpers are pure algorithms / I/O routines that
do not need to be part of the class interface; lifting them shrinks
the public API surface and clarifies the boundary between state
(SpinConstrain) and algorithm (free functions).

Changes
-------
- New header lambda_loop_helper.h declares 6 free function templates
  taking 'const SpinConstrain<TK>&' as first parameter.
- lambda_loop_helper.cpp: 6 explicit specializations on
  SpinConstrain<std::complex<double>> rewritten as free function
  templates with explicit instantiation for std::complex<double>.
- template_helpers.cpp: 6 corresponding no-op stubs for
  SpinConstrain<double> re-expressed as free function explicit
  specializations (preserves linker surface for the nspin=2 stub).
- spin_constrain.h: removed 6 member-function declarations; added
  public getters get_Mi() and get_current_sc_thr() so helpers can
  read internal state without friendship.
- spin_constrain.cpp: get_nat/get_ntype/get_decay_grad(itype)/
  get_decay_grad() promoted to const (required for const ref
  parameter); get_decay_grad(itype) uses map::find instead of
  operator[] to remain const-correct.
- lambda_loop.cpp: 7 call sites switched from
  'this->helper(...)' to 'helper(*this, ...)'.
- test/template_helpers_test.cpp: call sites updated.
- test/CMakeLists.txt: MODULE_LCAO_deltaspin_template_helpers now
  links lambda_loop_helper.cpp and basic_funcs.cpp (transitive
  deps of the new free function implementations).

Verification
------------
- 'make -j 30' in build_max_para_test: clean build, abacus +
  abacus_basic_para + all MODULE_LCAO_deltaspin_* targets linked.
- 'ctest -R deltaspin --output-on-failure': 5/5 tests passed
  (basic_func, spin_constrain, template_helpers, pw, core).

Out of scope
------------
PW-specific methods (cal_mi_pw, update_psi_charge_pw_*,
calculate_delta_hcc) and LCAO-specific helpers (cal_mi_lcao,
convert, calculate_MW, collect_MW) remain as member functions
for now; they will be lifted in subsequent phases.

* deltaspin: lift print_Mi / print_Mag_Force out of SpinConstrain class

Phase 2 of god-class slimming: lift the two table-printing member
functions print_Mi and print_Mag_Force out of SpinConstrain<TK> and
into free function templates in the spinconstrain namespace, alongside
the lambda-loop helpers landed in phase 1.

Motivation
----------
print_Mi / print_Mag_Force are pure formatting routines (FmtTable
output) that read Mi_ and lambda_ via the existing getters. They
do not belong on the class interface; lifting them further shrinks
the public API and consolidates all deltaspin printing in
lambda_loop_helper.{h,cpp}.

Changes
-------
- lambda_loop_helper.{h,cpp}: add print_Mi / print_Mag_Force free
  function templates. Both are generic (no per-TK stub needed);
  instantiated for std::complex<double> (real path) and double
  (nspin=2 stub path) so callers holding either TK can link.
- spin_constrain.{h,cpp}: remove print_Mi / print_Mag_Force member
  declarations and definitions; add get_atomLabels() getter so
  helpers can read the per-atom label vector.
- spin_constrain.{h,cpp}: promote check_atomCounts() to const (it
  only reads atomCounts and calls get_nat, both safe). Replaces
  std::map::iterator with const_iterator in two loops.
- ctrl_output_pw.cpp / ctrl_scf_lcao.cpp: update call sites from
  'sc.print_Mag_Force(ofs_running)' / 'sc.print_Mi(ofs_running)' to
  'spinconstrain::print_Mag_Force(sc, ofs_running)' /
  'spinconstrain::print_Mi(sc, ofs_running)'; add lambda_loop_helper.h
  include.

Verification
------------
- 'make -j 30' in build_max_para_test: clean build of abacus +
  abacus_basic_para + all MODULE_LCAO_deltaspin_* test targets.
- 'ctest -R deltaspin --output-on-failure': 5/5 tests passed.

Out of scope
------------
PW-specific methods (cal_mi_pw, update_psi_charge_pw_*,
calculate_delta_hcc), LCAO-specific helpers (cal_mi_lcao, convert,
calculate_MW, collect_MW) and accumulate_Mi_from_becp remain as
member functions for subsequent phases.

* Refactor: extract accumulate_Mi_from_becp as free function in mi_tools

Why:
- SpinConstrain<TK>::accumulate_Mi_from_becp does not depend on TK or any
  singleton state beyond Mi_ and get_spin_sign(ik); keeping it as a member
  unnecessarily couples it to the class template and singleton lifecycle.
- Factoring it out as a free function lets both LCAO and PW DeltaSpin paths
  call it without going through the SpinConstrain<TK> instantiation, and
  makes it independently unit-testable.

What changed:
- New files source/source_lcao/module_deltaspin/mi_tools.{h,cpp}:
  - pauli_to_moment moved here as inline free function (was inline in header)
  - accumulate_Mi_from_becp reimplemented as free function; Mi_ becomes an
    in/out reference parameter 'mi', ik replaced by caller-precomputed
    spin_sign (npol==2 callers pass 1), TK template parameter dropped.
  - Entry validates becp/wg_ik/nh_iat non-null, nkb/nbands positive,
    npol in {1,2}, spin_sign in {-1,1} via ModuleBase::WARNING_QUIT.
  - ModuleBase::ZERO replaced with local const std::complex<double>
    zero(0.0, 0.0), removing the source_base/constants.h include.
- spin_constrain.h: removed pauli_to_moment inline definition and the
  accumulate_Mi_from_becp member declaration.
- spin_constrain.cpp: removed the member function definition;
  get_spin_sign kept as member (it still reads npol_ and isk).
- cal_mw_from_lambda.cpp, deltaspin_pw_impl.cpp (3 call sites total):
  updated to precompute spin_sign and call the free function with mi.
- CMakeLists.txt: added mi_tools.cpp to the deltaspin OBJECT library.

Verification:
- cmake --build build_std_para -j4 : deltaspin OBJECT lib + abacus_std_para
  executable built successfully.
- Functional/ctest runs not executed (compile-only verification).

* deltaspin: remove redundant sc_parse_json.cpp

sc_parse_json.cpp contained only two explicit template instantiations
(template class spinconstrain::SpinConstrain<std::complex<double>> and
the double specialization) at global scope. The same instantiations
already exist at the end of spin_constrain.cpp (inside namespace
spinconstrain, lines 733-734), making this file dead code.

History: the file predates the instantiations being added to
spin_constrain.cpp; once those landed, sc_parse_json.cpp became
redundant but was never cleaned up. The misleading filename (suggests
JSON parsing) is also retired.

Verification: cmake --build build_std_para --target deltaspin -j4
built successfully; SpinConstrain<TK> symbols still resolve via the
in-file instantiations in spin_constrain.cpp.

* remove some PARAM usage

---------

Co-authored-by: ABACUS Dev <abacus-dev@example.com>
Co-authored-by: abacus_fixer <mohanchen@pku.eud.cn>

Author: 3 people

source/source_esolver/esolver_ks.cpp

@@ -190,6 +190,10 @@ void ESolver_KS::iter_init(UnitCell& ucell, const int istep, const int iter)
 
     iter_time = ModuleBase::get_time();
 
+    // Reset DeltaSpin RMS for this SCF iteration. If DeltaSpin is enabled, use 0
+    // (meaning "lambda loop not yet run this iteration"); otherwise -1 (no RMS column).
+    this->ds_rms_ = this->inp_->sc_mag_switch ? 0.0 : -1.0;
+
     if (this->inp_->esolver_type == "ksdft")
     {
         diag_ethr = hsolver::set_diagethr_ks(this->inp_->basis_type, this->inp_->esolver_type,
@@ -279,8 +283,8 @@ void ESolver_KS::iter_finish(UnitCell& ucell, const int istep, int& iter, bool &
     double duration = ModuleBase::get_duration(iter_time, ModuleBase::get_time());
 
     // print energies
-    elecstate::print_etot(ucell.magnet, *pelec, conv_esolver, iter, drho, 
-    dkin, duration, diag_ethr);
+    elecstate::print_etot(ucell.magnet, *pelec, conv_esolver, iter, drho,
+    dkin, duration, diag_ethr, 0, true, this->ds_rms_);
 
 
 #ifdef __RAPIDJSON

source/source_esolver/esolver_ks.h

@@ -70,6 +70,9 @@ class ESolver_KS : public ESolver_FP
     double scf_ene_thr;             //! scf energy threshold
     double drho;                    //! the difference between rho_in (before HSolver) and rho_out (After HSolver)
     double hsolver_error;           //! the error of HSolver
+    /// DeltaSpin RMS from the most recent lambda optimization loop; -1.0 means no DeltaSpin.
+    /// Set by ESolver_KS_LCAO after run_lambda_loop, read by ESolver_KS::iter_finish when calling print_etot.
+    double ds_rms_ = -1.0;
     int maxniter;                   //! maximum iter steps for scf
     int niter;                      //! iter steps actually used in scf
     bool oscillate_esolver = false; // whether esolver is oscillated

source/source_esolver/esolver_ks_lcao.cpp

@@ -430,18 +430,20 @@ void ESolver_KS_LCAO<TK, TR>::hamilt2rho_single(UnitCell& ucell, int istep, int
         spinconstrain::SpinConstrain<TK>& sc = spinconstrain::SpinConstrain<TK>::getScInstance();
         if (this->inp_->sc_lambda_strategy == "linear_scan")
         {
-            sc.run_lambda_linear_scan(iter - 1);
+            sc.run_lambda_linear_scan(iter - 1, GlobalV::ofs_running);
             skip_solve = true;
         }
         else if (!sc.mag_converged() && this->drho > 0 && this->drho < this->inp_->sc_scf_thr)
         {
-            sc.run_lambda_loop(iter - 1);
+            sc.run_lambda_loop(iter - 1, true, GlobalV::ofs_running);
+            this->ds_rms_ = sc.get_last_rms_error();
             sc.set_mag_converged(true);
             skip_solve = true;
         }
         else if (sc.mag_converged())
         {
-            sc.run_lambda_loop(iter - 1);
+            sc.run_lambda_loop(iter - 1, true, GlobalV::ofs_running);
+            this->ds_rms_ = sc.get_last_rms_error();
             skip_solve = true;
         }
     }

source/source_esolver/esolver_ks_pw.cpp

@@ -19,6 +19,7 @@
 #include "source_hamilt/module_xc/general_exx_info.h" // for General_Exx_Info type used via general_exx_info_
 #include "source_io/module_ctrl/ctrl_output_pw.h"  // mohan add 20250927
 #include "source_pw/module_pwdft/deltaspin_pw.h"   // mohan add 20250309
+#include "source_lcao/module_deltaspin/spin_constrain.h"
 #include "source_pw/module_pwdft/setup_pot.h"      // mohan add 20250929
 #include "source_pw/module_pwdft/update_cell_pw.h" // mohan add 20250309
 #include "source_pw/module_pwdft/setup_dftu_pw.h"  // mohan add 20250309
@@ -227,7 +228,14 @@ void ESolver_KS_PW<T, Device>::hamilt2rho_single(UnitCell& ucell, const int iste
     bool skip_charge = this->inp_->calculation == "nscf" ? true : false;
 
     // run the inner lambda loop to contrain atomic moments with the DeltaSpin method
-    bool skip_solve = pw::run_deltaspin_lambda_loop(iter - 1, this->drho, *this->inp_);
+    bool skip_solve = pw::run_deltaspin_lambda_loop(iter - 1, this->drho, *this->inp_, GlobalV::ofs_running);
+    if (skip_solve)
+    {
+        // Fetch the most recent DeltaSpin RMS for display in the SCF iteration table.
+        spinconstrain::SpinConstrain<std::complex<double>>& sc
+            = spinconstrain::SpinConstrain<std::complex<double>>::getScInstance();
+        this->ds_rms_ = sc.get_last_rms_error();
+    }
 
     if (!skip_solve)
     {

source/source_esolver/lcao_others.cpp

@@ -38,6 +38,8 @@ void ESolver_KS_LCAO<TK, TR>::others(BaseCell& basecell, const int istep)
     ModuleBase::timer::start("ESolver_KS_LCAO", "others");
 
     const std::string cal_type = this->inp_->calculation;
+    const std::string global_out_dir = PARAM.globalv.global_out_dir;
+    const bool gamma_only_local = PARAM.globalv.gamma_only_local;
 
     if (cal_type == "test_memory")
     {
@@ -78,7 +80,7 @@ void ESolver_KS_LCAO<TK, TR>::others(BaseCell& basecell, const int istep)
                                                    this->inp_->out_level,
                                                    orb_.get_rcutmax_Phi(),
                                                    ucell.infoNL->get_rcutmax_Beta(),
-                                                   PARAM.globalv.gamma_only_local);
+                                                   gamma_only_local);
 
     atom_arrange::search(PARAM.globalv.search_pbc,
                          GlobalV::ofs_running,
@@ -108,7 +110,7 @@ void ESolver_KS_LCAO<TK, TR>::others(BaseCell& basecell, const int istep)
     // (2)For each atom, calculate the adjacent atoms in different cells
     // and allocate the space for H(R) and S(R).
     // If k point is used here, allocate HlocR after atom_arrange.
-    this->RA.for_2d(ucell, this->gd, this->pv, PARAM.globalv.gamma_only_local, orb_.cutoffs());
+    this->RA.for_2d(ucell, this->gd, this->pv, gamma_only_local, orb_.cutoffs());
 
     // 2. density matrix extrapolation
 
@@ -175,14 +177,14 @@ void ESolver_KS_LCAO<TK, TR>::others(BaseCell& basecell, const int istep)
 
     // pelec should be initialized before these calculations
     elecstate::init_scf(ucell, this->Pgrid, this->sf.strucFac, this->locpp.numeric, 
-		    istep, PARAM.globalv.global_out_dir, *this->inp_, this->pelec);
+		    istep, global_out_dir, *this->inp_, this->pelec);
 
     // self consistent calculations for electronic ground state
     if (cal_type == "get_pchg")
     {
         std::cout << FmtCore::format("\n * * * * * *\n << Start %s.\n", "getting partial charge");
         Get_pchg_lcao get_pchg(this->psi, &(this->pv));
-        if (PARAM.globalv.gamma_only_local)
+        if (gamma_only_local)
         {
             get_pchg.begin(this->chr.rho,
                            this->pelec->wg,
@@ -196,7 +198,7 @@ void ESolver_KS_LCAO<TK, TR>::others(BaseCell& basecell, const int istep)
                            this->Pgrid,
                            &this->gd,
                            this->kv,
-                           PARAM.globalv.global_out_dir,
+                           global_out_dir,
                            GlobalV::ofs_running);
         }
         else
@@ -215,7 +217,7 @@ void ESolver_KS_LCAO<TK, TR>::others(BaseCell& basecell, const int istep)
                            this->Pgrid,
                            &this->gd,
                            this->kv,
-                           PARAM.globalv.global_out_dir,
+                           global_out_dir,
                            GlobalV::ofs_running,
                            this->inp_->if_separate_k,
                            this->chr.ngmc);
@@ -226,7 +228,7 @@ void ESolver_KS_LCAO<TK, TR>::others(BaseCell& basecell, const int istep)
     {
         std::cout << FmtCore::format("\n * * * * * *\n << Start %s.\n", "getting wave function");
         Get_wf_lcao get_wf(this->pelec);
-        if (PARAM.globalv.gamma_only_local)
+        if (gamma_only_local)
         {
             get_wf.begin(ucell,
                          this->psi,
@@ -241,7 +243,7 @@ void ESolver_KS_LCAO<TK, TR>::others(BaseCell& basecell, const int istep)
                          this->inp_->nbands,
                          this->inp_->nspin,
                          PARAM.globalv.nlocal,
-                         PARAM.globalv.global_out_dir,
+                         global_out_dir,
                          GlobalV::ofs_running);
         }
         else
@@ -259,7 +261,7 @@ void ESolver_KS_LCAO<TK, TR>::others(BaseCell& basecell, const int istep)
                          this->inp_->nbands,
                          this->inp_->nspin,
                          PARAM.globalv.nlocal,
-                         PARAM.globalv.global_out_dir,
+                         global_out_dir,
                          GlobalV::ofs_running);
         }
         std::cout << FmtCore::format(" >> Finish %s.\n * * * * * *\n", "getting wave function");

source/source_estate/elecstate_print.cpp

@@ -44,7 +44,8 @@ void print_scf_iterinfo(const std::string& ks_solver,
                         const std::vector<double>& drho,
                         const int& wrho,
                         const double& time,
-                        const int& wtime)
+                        const int& wtime,
+                        const double& ds_rms)
 {
     std::map<std::string, std::string> iter_header_dict
         = {{"cg", "CG"},
@@ -91,6 +92,12 @@ void print_scf_iterinfo(const std::string& ks_solver,
     {
         td_fmt.emplace_back(" %" + std::to_string(wrho) + ".4e");
     }
+    // DeltaSpin RMS column (optional, same width/format as DRHO/DKIN)
+    if (ds_rms >= 0)
+    {
+        th_fmt.emplace_back(" %" + std::to_string(wrho) + "s");
+        td_fmt.emplace_back(" %" + std::to_string(wrho) + ".4e");
+    }
     // time column, trivial
     th_fmt.emplace_back(" %" + std::to_string(wtime) + "s\n");
     td_fmt.emplace_back(" %" + std::to_string(wtime) + ".2f\n");
@@ -132,6 +139,13 @@ void print_scf_iterinfo(const std::string& ks_solver,
         titles.push_back(FmtCore::center("DKIN", wrho));
         values.push_back(drho[1]);
     }
+    // DeltaSpin RMS column: shown only when a valid RMS value is provided (>= 0).
+    // Placed after DKIN (if any) and before TIME.
+    if (ds_rms >= 0)
+    {
+        titles.push_back(FmtCore::center("RMS", wrho));
+        values.push_back(ds_rms);
+    }
     titles.push_back(FmtCore::center("TIME/s", wtime));
     values.push_back(time);
     std::string buf;
@@ -168,7 +182,8 @@ void print_etot(const Magnetism& magnet,
                 const double& duration,
                 const double& pw_diag_thr,
                 const double& avg_iter,
-                const bool print)
+                const bool print,
+                const double& ds_rms)
 {
     ModuleBase::TITLE("energy", "print_etot");
     const int iter = iter_in;
@@ -395,7 +410,8 @@ void print_etot(const Magnetism& magnet,
                                       drho,
                                       12,
                                       duration,
-                                      6);
+                                      6,
+                                      ds_rms);
     }
     return;
 }

source/source_estate/elecstate_print.h

@@ -17,6 +17,7 @@ namespace elecstate
                     const double& duration,
                     const double& pw_diag_thr = 0,
                     const double& avg_iter = 0,
-                    bool print = true);
+                    bool print = true,
+                    const double& ds_rms = -1.0);
 }
 #endif

source/source_io/module_ctrl/ctrl_output_pw.cpp

@@ -10,6 +10,7 @@
 #include "../module_wf/get_wf_pw.h"
 #include "../module_wf/write_wfc_pw.h" // use write_wfc_pw
 #include "source_base/formatter.h"
+#include "source_lcao/module_deltaspin/lambda_loop_helper.h"
 #include "source_lcao/module_deltaspin/spin_constrain.h"
 #include "source_pw/module_pwdft/elecond.h"
 #include "source_pw/module_pwdft/onsite_proj.h" // use projector
@@ -214,7 +215,7 @@ void ModuleIO::ctrl_scf_pw(const int istep,
     {
         spinconstrain::SpinConstrain<std::complex<double>>& sc = spinconstrain::SpinConstrain<std::complex<double>>::getScInstance();
         sc.cal_mi_pw();
-        sc.print_Mag_Force(GlobalV::ofs_running);
+        spinconstrain::print_Mag_Force(sc, GlobalV::ofs_running);
     }
 
     //------------------------------------------------------------------

source/source_io/module_ctrl/ctrl_scf_lcao.cpp

@@ -25,6 +25,7 @@
 #include "../module_dm/write_dmr.h"                           // use ModuleIO::write_dmr()
 #include "../module_dos/write_dos_lcao.h"                      // use ModuleIO::write_dos_lcao()
 #include "../module_wf/write_wfc_nao.h"                       // use ModuleIO::write_wfc_nao()
+#include "source_lcao/module_deltaspin/lambda_loop_helper.h"   // print_Mi / print_Mag_Force free functions
 #include "source_lcao/module_deltaspin/spin_constrain.h"   // use spinconstrain::SpinConstrain<TK>
 #include "source_lcao/module_operator_lcao/ekinetic.h" // use hamilt::EKinetic
 #ifdef __MLALGO
@@ -554,8 +555,8 @@ void ModuleIO::ctrl_scf_lcao(UnitCell& ucell,
     {
         spinconstrain::SpinConstrain<TK>& sc = spinconstrain::SpinConstrain<TK>::getScInstance();
         sc.cal_mi_lcao(istep);
-        sc.print_Mi(GlobalV::ofs_running);
-        sc.print_Mag_Force(GlobalV::ofs_running);
+        spinconstrain::print_Mi(sc, GlobalV::ofs_running);
+        spinconstrain::print_Mag_Force(sc, GlobalV::ofs_running);
     }
 
     //------------------------------------------------------------------

source/source_lcao/module_deltaspin/CMakeLists.txt

@@ -8,8 +8,8 @@ list(APPEND objects
     cal_mw_from_lambda.cpp
     template_helpers.cpp
     deltaspin_lcao.cpp
-    sc_parse_json.cpp
     cal_mw_helper.cpp
+    mi_tools.cpp
 )
 
 add_library(