• Customizing wlog file
  • Example
• Customizing wdata files
  • Example

Customizing wlog file

For reporting basic quantities (like particle number, energy, etc) W-SLDA code uses wlog file. It is a txt file produced by the function int logger( ) from logger.h file. The user can modify this file depending on the specifics of a given problem.

Example

Suppose that in addition to defined by default variables, the user needs to print out a new variable:

\Delta_{\textrm{avg}}(t) = \dfrac{\int |\Delta(\bm{r},t)|(n_a(\bm{r},t)+n_b(\bm{r},t))\,d\bm{r}}{\int (n_a(\bm{r},t)+n_b(\bm{r},t))\,d\bm{r}}

In the first step, we define the new variable

int add_custom_variable_to_wdata_metadata(wdata_metadata *wdmd,
           double *params, size_t extra_data_size, void *extra_data)
{
    // To add a variable use this template
    //                       var_name       type    unit
    wdata_variable var1 = {"E_flow", "real", "none", "wdat"}; // scalar variable
    wdata_add_variable(wdmd, &var1);

    return 0;
}

which is (weighted) average value of the delta. This can be done by adding to logger(..):

int ixyz;
int lNXYZ = h_potentials.blocklength;
double delta_avg=0.0, Ntot = 0.0; 
for(ixyz=0; ixyz<lNXYZ; ixyz++) delta_avg+=cabs(h_potentials.delta[ixyz])*(h_densities.rho_a[ixyz]+h_densities.rho_b[ixyz]);
for(ixyz=0; ixyz<lNXYZ; ixyz++) Ntot+=h_densities.rho_a[ixyz]+h_densities.rho_b[ixyz];
delta_avg /= Ntot;

and supplementing printf statement with appropriate entry, like:

    // add entry
    fprintf(log, "%6d %18.10g %18.10g 
                %18.10g %18.10g %18.10g 
                %18.10g %18.10g %18.10g 
                %18.10g %18.10g %18.10g 
                %18.10g %18.10g %18.10g 
                %18.10g %18.10g %18.10g %10.2f %20s\n",
                                 //  <-- HERE
        it, // 1
        npart[SPINA], // 2
        npart[SPINB], // 3
        npart[SPINA]+npart[SPINB], // 4
        E_tot/Effg, // 5
        energy[EKIN]/Effg, // 6
        energy[EPOT]/Effg, // 7
        energy[EPAIR]/Effg, // 8
        energy[ECURRENT]/Effg, // 9
        energy[EPOTEXT]/Effg, //10
        energy[EPAIREXT]/Effg, //11
        energy[EVELEXT]/Effg, //12
        mu[SPINA]/eF, //13
        mu[SPINB]/eF, //14
        kF, // 15
        eF, // 16
        Effg, // 17
        delta_avg, // 18 <-- HERE
        logger_get_time_from_last_entry(), //19
        buffer
    );

Customizing wdata files

Functionality introduced with API_VERSION>=20231218

The logger allows also to define new variables of results W-data set. It is done in two steps:

1. Adding a definition of a new variable via add_custom_variable_to_wdata_metadata function.
2. Adding a body of function write_custom_variable_to_wdata_set that creates and writes the new variable to wdata set.

Example

To demonstrate the functionality of extending wdata set by new variables, let us add new variable which is density of the flow energy

E_{flow}(\bm{r}) = \frac{\bm{j}_a^2(\bm{r})}{2n_a(\bm{r})} + \frac{\bm{j}_b^2(\bm{r})}{2n_b(\bm{r})}

In the first step, we define the new variable with the name E_flow

int add_custom_variable_to_wdata_metadata(wdata_metadata *wdmd,
           double *params, size_t extra_data_size, void *extra_data)
{
    wdata_variable var1 = {"E_flow", "real", "none", "wdat"}; // scalar variable
    wdata_add_variable(wdmd, &var1);

    return 0;
}

Next, we construct the variable and write it to the wdata set

int write_custom_variable_to_wdata_set(wdata_metadata *wdmd,
           int it,
           wslda_density h_densities, wslda_potential h_potentials,
           double kF, double *mu,
           double *params, size_t extra_data_size, void *extra_data)
{
    // DETERMINE LOCAL SIZES OF ARRAYS (CODE DIMENSIONALITY DEPENDENT)
    int lNX=h_densities.nx, lNY=h_densities.ny, lNZ=h_densities.nz; // local sizes
    int ix, iy, iz, ixyz;

    double *E_flow = (double *)malloc(lNX*lNY*lNZ*sizeof(double)); // allocate memory for the variable

    // ITERATE OVER ALL POINTS
    ixyz=0;
    for(ix=0; ix<lNX; ix++) for(iy=0; iy<lNY; iy++) for(iz=0; iz<lNZ; iz++)
    {
        double x = DX*(ix-lNX/2);
        double y = DY*(iy-lNY/2); // for 1d code y will be always 0
        double z = DZ*(iz-lNZ/2); // for 1d and 2d codes z will be always 0

        // construst the variable
        double ja2 = pow(h_densities.j_a_x[ixyz],2) + pow(h_densities.j_a_y[ixyz],2) + pow(h_densities.j_a_z[ixyz],2);
        double jb2 = pow(h_densities.j_b_x[ixyz],2) + pow(h_densities.j_b_y[ixyz],2) + pow(h_densities.j_b_z[ixyz],2);
        E_flow[ixyz] = ja2 / (2.*h_densities.rho_a[ixyz]) + jb2 / (2.*h_densities.rho_b[ixyz]);

        ixyz++; // go to the next point, it should be the last line of the triple loop
    }

    // to add variable to binary file use this function
    wdata_write_cycle(wdmd, "E_flow", E_flow);

    free(E_flow); // clear memory

    return 0;
}