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/*******************************************************************************
*
* McStas, neutron ray-tracing package
* Copyright(C) 2007 Risoe National Laboratory.
*
* %I
* Written by: Mads Bertelsen
* Date: 20.08.15
* Version: $Revision: 0.1 $
* Origin: ESS DMSC
*
* This process dos nothing and is used for testing
*
* %D
*
* This process dos nothing and is used for testing
*
* Part of the Union components, a set of components that work together and thus
* sperates geometry and physics within McStas.
* The use of this component requires other components to be used.
*
* 1) One specifies a number of processes using process components like this one
* 2) These are gathered into material definitions using Union_make_material
* 3) Geometries are placed using Union_box / Union_cylinder, assigned a material
* 4) A Union_master component placed after all of the above
*
* Only in step 4 will any simulation happen, and per default all geometries
* defined before the master, but after the previous will be simulated here.
*
* There is a dedicated manual available for the Union_components
*
*
* Algorithm:
* Described elsewhere
*
* %P
* INPUT PARAMETERS:
* sigma: [barns] Scattering cross section
* unit_cell_volume: [AA^3] Unit cell volume
*
* CALCULATED PARAMETERS:
* Non_storage // Important to update this output paramter
* effective_my_scattering // Variable used in initialize
*
* %L
*
* %E
******************************************************************************/
DEFINE COMPONENT Non_process // Remember to change the name of process here
SETTING PARAMETERS(sigma=5.08,packing_factor=1,unit_cell_volume=13.8,interact_fraction=-1, string init="init")
SHARE
%{
#ifndef Union
#error "The Union_init component must be included before this Non_process component"
#endif
// Very important to add a pointer to this struct in the union-lib.c file
struct Non_physics_storage_struct{
// Variables that needs to be transfered between any of the following places:
// The initialize in this component
// The function for calculating my
// The function for calculating scattering
// Avoid duplicates of output parameters and setting parameters in naming
double my_scattering;
};
// Function for calculating my, the inverse penetration depth (for only this scattering process).
// The input for this function and its order may not be changed, but the names may be updated.
int Non_physics_my(double *my, double *k_initial, union data_transfer_union data_transfer, struct focus_data_struct *focus_data, _class_particle *_particle) {
// *k_initial is a pointer to a simple vector with 3 doubles, k[0], k[1], k[2] which describes the wavevector
// Simple case, just retrive the parameter saved from initialize
*my = data_transfer.pointer_to_a_Non_physics_storage_struct->my_scattering;
return 1;
};
// Function that provides description of a basic scattering event.
// Do not change the
int Non_physics_scattering(double *k_final, double *k_initial, double *weight, union data_transfer_union data_transfer, struct focus_data_struct *focus_data, _class_particle *_particle) {
k_final[0] = k_initial[0];
k_final[1] = k_initial[1];
k_final[2] = k_initial[2];
return 1; // return 1 is sucess, return 0 is failure, and the ray will be absorbed.
// failure should not happen, as this function will only be called when
// the cross section for the current k_initial is above zero.
// There is access to the data_transfer from within the scattering function
// In this case the only variable is my, but it could be read by:
// double my = data_transfer.pointer_to_a_Non_physics_storage_struct->my_scattering;
// One can assume that if the scattering function is running, the my fuction was
// executed just before and for the same k_initial.
};
// These lines help with future error correction, and tell other Union components
// that at least one process have been defined.
#ifndef PROCESS_DETECTOR
// Obsolete
//struct pointer_to_global_process_list global_process_list = {0,NULL};
#define PROCESS_DETECTOR dummy
#endif
%}
DECLARE
%{
// Declare for this component, to do calculations on the input / store in the transported data
struct Non_physics_storage_struct Non_storage; // Replace Non with your own name here
// Variables needed in initialize of this function.
double effective_my_scattering;
// Needed for transport to the main component, will be the same for all processes
struct global_process_element_struct global_process_element;
struct scattering_process_struct This_process;
%}
INITIALIZE
%{
// Initialize done in the component
effective_my_scattering = ((packing_factor/unit_cell_volume) * 100 * sigma);
Non_storage.my_scattering = effective_my_scattering;
// Need to specify if this process is isotropic
This_process.non_isotropic_rot_index = -1; // Yes (powder)
//This_process.non_isotropic_rot_index = 1; // No (single crystal)
// Packing the data into a structure that is transported to the main component
This_process.data_transfer.pointer_to_a_Non_physics_storage_struct = &Non_storage;
This_process.probability_for_scattering_function = &Non_physics_my;
This_process.scattering_function = &Non_physics_scattering;
// This will be the same for all process's, and can thus be moved to an include.
sprintf(This_process.name,"%s",NAME_CURRENT_COMP);
This_process.process_p_interact = interact_fraction;
rot_copy(This_process.rotation_matrix,ROT_A_CURRENT_COMP);
sprintf(global_process_element.name,"%s",NAME_CURRENT_COMP);
global_process_element.component_index = INDEX_CURRENT_COMP;
global_process_element.p_scattering_process = &This_process;
if (_getcomp_index(init) < 0) {
fprintf(stderr,"Non_process:%s: Error identifying Union_init component, %s is not a known component name.\n",
NAME_CURRENT_COMP, init);
exit(-1);
}
struct pointer_to_global_process_list *global_process_list = COMP_GETPAR3(Union_init, init, global_process_list);
add_element_to_process_list(global_process_list,global_process_element);
%}
TRACE
%{
// Trace should be empty, the simulation is done in Union_master
%}
END
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