Drake package example consumer

main.cc

// See https://github.com/RobotLocomotion/drake/pull/5448

#include <iostream>

#include <Eigen/Dense>

#include "drake/systems/framework/diagram.h"
#include "drake/systems/primitives/adder.h"

using namespace drake::systems;

int main(int argc, char* argv[]) {
  const int kNumInputs = 2;
  const int kSize = 1;
  Adder<double> adder(kNumInputs, kSize);
  std::unique_ptr<Context<double>> context = adder.CreateDefaultContext();
  std::unique_ptr<SystemOutput<double>> output = adder.AllocateOutput(*context);
  
  context->FixInputPort(0, BasicVector<double>::Make({7}));
  context->FixInputPort(1, BasicVector<double>::Make({11}));

  adder.CalcOutput(*context, output.get());
  std::cout << std::to_string(output->get_vector_data(0)->GetAtIndex(0)) << std::endl;
  return 0;
}