add annotation and minor changes

Co-authored-by: kirk0830 <[email protected]>

Author: maki49

source/module_lr/esolver_lrtd_lcao.cpp

@@ -126,7 +126,13 @@ void LR::ESolver_LR<T, TR>::set_dimension()
     if (input.ri_hartree_benchmark == "aims" && !input.aims_nbasis.empty())
     {
         this->nbasis = [&]() -> int { int nbas = 0; for (int it = 0;it < ucell.ntype;++it) { nbas += ucell.atoms[it].na * input.aims_nbasis[it]; };return nbas;}();
-        this->nbasis = std::inner_product(input.aims_nbasis.begin(), input.aims_nbasis.end(), ucell.atoms, 0, std::plus<int>(), [](const int& a, const Atom& b) { return a * b.na; });
+        // calculate total number of basis funcs, see https://en.cppreference.com/w/cpp/algorithm/inner_product
+        this->nbasis = std::inner_product(input.aims_nbasis.begin(), /* iterator1.begin */
+                                          input.aims_nbasis.end(),  /* iterator1.end */
+                                          ucell.atoms,  /* iterator2.begin */
+                                          0,  /* init value */
+                                          std::plus<int>(), /* iter op1 */
+                                          [](const int& a, const Atom& b) { return a * b.na; }); /* iter op2 */
         std::cout << "nbasis from aims: " << this->nbasis << std::endl;
     }
 }

source/module_lr/potentials/pot_hxc_lrtd.cpp

@@ -36,7 +36,7 @@ namespace LR
             {
                 const std::set<std::string> lda_xc = { "lda", "pwlda" };
                 assert(lda_xc.count(this->xc_kernel_));
-                const int n_component = (1 == nspin) ? 1 : 3;
+                const int n_component = (1 == nspin) ? 1 : 3;   // spin components of fxc: (uu, ud=du, dd) when nspin=2
                 this->xc_kernel_components_.v2rho2.resize(n_component * nrxx);
                 // read fxc adn add to xc_kernel_components
                 assert(lr_init_xc_kernel.size() >= n_component + 1);

source/module_lr/potentials/xc_kernel.cpp

@@ -37,7 +37,7 @@ void LR::KernelXC::f_xc_libxc(const int& nspin, const double& omega, const doubl
 
     // -----------------------------------------------------------------------------------
     // for GGA
-    const bool is_gga = std::any_of(funcs.begin(), funcs.end(), [](const xc_func_type& f)->bool { return f.info->family == XC_FAMILY_GGA || f.info->family == XC_FAMILY_HYB_GGA; });
+    const bool is_gga = std::any_of(funcs.begin(), funcs.end(), [](const xc_func_type& f) { return f.info->family == XC_FAMILY_GGA || f.info->family == XC_FAMILY_HYB_GGA; });
 
     std::vector<std::vector<ModuleBase::Vector3<double>>> gradrho;  // \nabla \rho
     std::vector<double> sigma;  // |\nabla\rho|^2