examples/dependency_management_example.cpp

Example usage of CompositeParamAdapter to manage parameter dependencies.

Example usage of CompositeParamAdapter to manage parameter dependencies.This example demonstrates how to add a dependent block based on multiple source blocks and how to trigger an update manually.

#include "CompositeParamAdapter.h"
#include "Parameters.h"
#include <iostream>
 
int main() {
    // Assume the Parameters system is already initialized
    
    // Define the sources: blocks from different parameter types
    std::unordered_map<ParameterType, std::vector<std::string>> sources = {
        {ParameterType::SM, {"GAUGE", "MASS"}}
    };
 
    // Define the recalculation function
    auto recalculate = [](const std::unordered_map<std::string, std::shared_ptr<Block>>& src_blocks,
                           std::shared_ptr<DependentBlock> dep_block) {
        double alpha_em = src_blocks.at("GAUGE")->retrieve(LhaID(1))->get_val();
        double mass_w  = src_blocks.at("MASS")->retrieve(LhaID(24))->get_val();
        
        dep_block->store_or_assign(LhaID(100), std::make_shared<Parameter>(ParamId("NEWBLOCK", 100), alpha_em + mass_w, 0., 0.));
    };
 
    // Create the adapter and add the dependent block
    CompositeParamAdapter adapter;
    adapter.add_block_dependency("NEWBLOCK", sources, ParameterType::SM, recalculate);
 
    // Trigger a manual update
    adapter.update_dependency("NEWBLOCK", ParameterType::SM);
 
    // Access and print the new value
    auto value = Parameters::GetInstance(ParameterType::SM)->operator()("NEWBLOCK", LhaID(100));
    std::cout << "Combined value = " << value << std::endl;
 
    return 0;
}