add stochastic DFT parameters to input-main.md

Author: Qianruipku

docs/input-main.md

@@ -8,7 +8,7 @@
 
 - [System variables](#system-variables)
 
-    [suffix](#suffix) | [ntype](#ntype) | [calculation](#calculation) | [symmetry](#symmetry) | [kpar](#kpar) | [latname](#latname) | [init_wfc](#init_wfc) | [init_chg](#init_chg) | [init_vel](#init_vel) | [nelec](#nelec) | [tot_magnetization](#tot-magnetization) | [dft_functional](#dft-functional) | [pseudo_type](#pseudo-type) |  [pseudo_rcut](#pseudo-rcut) | [pseudo_mesh](#pseudo_mesh) | [mem_saver](#mem-saver) | [diago_proc](#diago_proc) | [nbspline](#nbspline)
+    [suffix](#suffix) | [ntype](#ntype) | [calculation](#calculation) | [symmetry](#symmetry) | [kpar](#kpar) | [bndpar](#bndpar) | [latname](#latname) | [init_wfc](#init_wfc) | [init_chg](#init_chg) | [init_vel](#init_vel) | [nelec](#nelec) | [tot_magnetization](#tot-magnetization) | [dft_functional](#dft-functional) | [pseudo_type](#pseudo-type) |  [pseudo_rcut](#pseudo-rcut) | [pseudo_mesh](#pseudo_mesh) | [mem_saver](#mem-saver) | [diago_proc](#diago_proc) | [nbspline](#nbspline)
 
 - [Variables related to input files](#variables-related-to-input-files)
 
@@ -24,7 +24,7 @@
 
 - [Electronic structure](#electronic-structure)
 
-    [basis_type](#basis-type) | [ks_solver](#ks-solver) | [nbands](#nbands) | [nbands_istate](#nbands-istate) | [nspin](#nspin) | [occupations](#occupations) | [smearing_method](#smearing_method) | [smearing_sigma](#smearing_sigma) | [mixing_type](#mixing-type) | [mixing_beta](#mixing-beta) | [mixing_ndim](#mixing-ndim) | [mixing_gg0](#mixing-gg0) | [gamma_only](#gamma-only) | [printe](#printe) | [scf_nmax](#scf_nmax) | [scf_thr](#scf_thr) | [chg_extrap](#chg_extrap)
+    [basis_type](#basis-type) | [ks_solver](#ks-solver) | [nbands](#nbands) | [nbands_sto](#nbands_sto) | [nbands_istate](#nbands-istate) | [nspin](#nspin) | [occupations](#occupations) | [smearing_method](#smearing_method) | [smearing_sigma](#smearing_sigma) | [mixing_type](#mixing-type) | [mixing_beta](#mixing-beta) | [mixing_ndim](#mixing-ndim) | [mixing_gg0](#mixing-gg0) | [gamma_only](#gamma-only) | [printe](#printe) | [scf_nmax](#scf_nmax) | [scf_thr](#scf_thr) | [chg_extrap](#chg_extrap) | [nche_sto](#nche_sto) | [emin_sto](#emin_sto) | [emax_sto](#emax_sto) | [seed_sto](#seed_sto)
 
 - [Geometry relaxation](#geometry-relaxation)
 
@@ -150,6 +150,12 @@ This part of variables are used to control general system parameters.
 - **Description**: devide all processors into kpar groups, and k points will be distributed among each group. The value taken should be less than or equal to the number of k points as well as the number of MPI threads.
 - **Default**: 1
 
+#### bndpar
+
+- **Type**: Integer
+- **Description**: devide all processors into bndpar groups, and bands (only stochastic orbitals now) will be distributed among each group. 
+- **Default**: 1
+
 #### latname
 
 - **Type**: String
@@ -453,6 +459,14 @@ calculations.
   - nspin=1: 1.2\*occupied_bands, occupied_bands+10)
   - nspin=2: max(1.2\*nelec, nelec+20)
 
+#### nbands_sto
+
+- **Type**: Integer
+- **Description**: 
+  - nbands_sto>0: Number of stochastic orbitals to calculate in stochastic DFT (SDFT) or mix stochastic-deterministic (MDFT). More bands obtain more precise results or smaller stochastic errors ($ \propto 1/\sqrt{N_{\chi}}$); 
+  - nbands_sto=0: Complete basis will be used to replace stochastic orbitals with the Chebyshev method (CT) and it will get the results the same as KSDFT without stochastic errors.
+- **Default**: 0
+
 #### nbands_istate
 
 - **Type**: Integer
@@ -551,6 +565,32 @@ calculations.
   - second-order: second-order extrapolation
 - **Default**:atomic
 
+#### nche_sto
+
+- **Type**: Integer
+- **Description**: Chebyshev expansion orders for SDFT, MDFT, CT methods.
+- **Default**:5
+
+#### emin_sto
+
+- **Type**: Real
+- **Description**: Trial energy to guess the lower bound of eigen energies of the Hamitonian Operator $\hat{H}$. The unit is Ry.
+- **Default**:0.0
+
+#### emax_sto
+
+- **Type**: Real
+- **Description**: Trial energy to guess the upper bound of eigen energies of the Hamitonian Operator $\hat{H}$. The unit is Ry.
+- **Default**:0.0
+
+#### seed_sto
+
+- **Type**: Integer
+- **Description**: The random seed to generate stochastic orbitals.
+  - seed_sto>=0: Stochastic orbitals have the form of $\exp(i2\pi\theta(G))$, where $\theta$ is a uniform distribution in $(0,1)$. If seed_sto=0, the seed is decided by time(NULL).
+  - seed_sto<=-1: Stochastic orbitals have the form of $\pm1$ with the equal probability. If seed_sto=-1, the seed is decided by time(NULL).
+- **Default**:0
+
 ### Geometry relaxation
 
 This part of variables are used to control the geometry relaxation.

source/input.cpp

@@ -138,7 +138,7 @@ void Input::Default(void)
     nbands_sto = 0;
     nbands_istate = 5;
     pw_seed = 1;
-    nche_sto = 0;
+    nche_sto = 5;
     seed_sto = 0;
     bndpar = 1;
     kpar = 1;

source/src_pw/sto_che.cpp

@@ -38,9 +38,9 @@ void Stochastic_Chebychev::init(int ndmax_in, int norder_in)
     this->ndmax = ndmax_in;
     this->norder = norder_in;
 
-    if(norder<5)
+    if(norder<1)
     {
-        ModuleBase::WARNING_QUIT("Stochastic_Chebychev", "The Chebychev expansion order should be at least 5!");
+        ModuleBase::WARNING_QUIT("Stochastic_Chebychev", "The Chebychev expansion order should be at least 1!");
     }
 
     assert(extend >= 1);

source/src_pw/sto_iter.cpp

@@ -131,7 +131,7 @@ void Stochastic_Iter::checkemm(const int& ik, int &iter, Stochastic_WF& stowf)
         Stochastic_hchi:: Emax = Emax;
         if(change)
 	    {
-	    	std::cout<<"New Emax "<<Stochastic_hchi:: Emax<<" ; new Emin "<<Stochastic_hchi:: Emin<<std::endl;
+	    	GlobalV::ofs_running<<"New Emax "<<Stochastic_hchi:: Emax<<" ; new Emin "<<Stochastic_hchi:: Emin<<std::endl;
 	    }
         change = false;
     }
@@ -224,7 +224,7 @@ void Stochastic_Iter::itermu(int &iter)
     double tmpre;
     tmpre = stoche.coef[stoche.norder-1] * spolyv[stoche.norder-1];
     MPI_Allreduce(MPI_IN_PLACE, &tmpre, 1, MPI_DOUBLE, MPI_SUM , MPI_COMM_WORLD);
-    GlobalV::ofs_running<<"Chebyshev Precision: "<<abs(tmpre/targetne)<<std::endl;
+    GlobalV::ofs_running<<"Chebyshev Precision: "<<abs(tmpre/targetne)*1e9<<"E-9"<<std::endl;
     if(tmpre/targetne > GlobalV::SCF_THR )
     {
         stringstream ss;