Examples to use slice postprocessing functions based on medcoupling

Examples for the definition of a new slices

    /* Add a slice plane intersecting the origin (0,0,0) with a normal
     * along the Z axis (0,0,1), and length of 1m along both axis.
     *
     * If code_saturne is compiled without MEDCoupling, this call will
     * raise an error during runtime.
     */
    cs_real_t o[3] = {0.};
    cs_real_t n[3] = {0., 0., 1.};
    cs_medcoupling_postprocess_add_plane_slice("slice_OZ",  /* Name of the slice */
                                               "all[]",     /* Selection criteria for cells to intersect */
                                               o,           /* Slice origin point */
                                               n,           /* Slice normal vector */
                                               1.,          /* Plane length along first axis */
                                               1.);         /* Plane length along second axis */

    /* Add a disc slice intersecting the origin (0,0,0) with a normal
     * along the Z axis (0,0,1), and a radius of 0.5m.
     *
     * If code_saturne is compiled without MEDCoupling, this call will
     * raise an error during runtime.
     */
    cs_real_t o[3] = {0.};
    cs_real_t n[3] = {0., 0., 1.};
    cs_medcoupling_postprocess_add_disc_slice("disc1",  /* Name of the slice */
                                              "all[]",     /* Selection criteria for cells to intersect */
                                               o,           /* Slice origin point */
                                               n,           /* Slice normal vector */
                                               0.5,         /* Disc radius */
                                               -1);         /* Number of sectors. if < 0 default value of 36 is used. */

    /* Add a slice plane intersecting the origin (0,0,0) with a normal
     * along the Z axis (0,0,1), and length of 1m along both axis.
     *
     * If code_saturne is compiled without MEDCoupling, this call will
     * raise an error during runtime.
     */
    cs_real_t o[3] = {0.};
    cs_real_t n[3] = {0., 0., 1.};
    cs_medcoupling_postprocess_add_annulus_slice("annulus_slice", /* Name of the slice */
                                                 "all[]",     /* Selection criteria for cells to intersect */
                                                 o,           /* Slice origin point */
                                                 n,           /* Slice normal vector */
                                                 0.2,         /* Inner radius (hole)  */
                                                 0.5,         /* Outer radius */
                                                 72);         /* Number of sectors. if < 0 default value of 36 is used */

Compute the integral of a scalar

    /* Compute an integral of a given scalar over the slice "annulus_slice" */
    cs_real_t *cpro_scal = cs_field("my_scalar")->val;
 
    [[maybe_unused]] cs_real_t int_val
      = cs_medcoupling_slice_scalar_integral("annulus_slice", /* Name of the slice */
                                             cpro_scal);      /* Pointer to scalar values */

Compute the mean value of a scalar

    /* Compute mean of a scalar over the slice "slice_OZ" */
    cs_real_t *cpro_scal = cs_field("my_scalar")->val;
 
    [[maybe_unused]] cs_real_t mean_val
      = cs_medcoupling_slice_scalar_mean("slice_OZ", cpro_scal);

Example for the computation Tbulk over a given slice

    /* Compute t_bulk of a disc slice.
     * t_bulk = Int(T * cp * rho * <u|n>) / Int(cp * rho * <u|n>)
     */
 
    const cs_lnum_t n_cells = domain->mesh->n_cells;
    cs_array<cs_real_t> rho_cp(n_cells);
 
    for (cs_lnum_t c_id = 0; c_id < n_cells; c_id++)
      rho_cp[c_id] = CS_F_(cp)->val[c_id] * CS_F_(rho)->val[c_id];
 
    cs_real_3_t *cvar_vel = (cs_real_3_t *)CS_F_(vel)->val;
 
    cs_real_t t_bulk = cs_medcoupling_slice_scalar_mean_weighted("disc1",
                                                                 CS_F_(t)->val,
                                                                 rho_cp,
                                                                 cvar_vel);