examples/helloworld_cost_function.h

// Ceres Solver - A fast non-linear least squares minimizer
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// http://code.google.com/p/ceres-solver/
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// Author: darius.rueckert@fau.de (Darius Rueckert)
//
#include "ceres/codegen/codegen_cost_function.h"

namespace helloworld {

struct HelloWorldCostFunction : public ceres::CodegenCostFunction<1, 1> {
  // We need a default constructor, because code is generated for the cost
  // functor and not a specific instantiation of it.
  HelloWorldCostFunction() = default;
  explicit HelloWorldCostFunction(double target_value)
      : target_value_(target_value) {}

  template <typename T>
  bool operator()(const T* x, T* residual) const {
    residual[0] = CERES_LOCAL_VARIABLE(T, target_value_) - x[0];
    return true;
  }

// The include file name is automatically generated as
// "<output_dir>/<lower_case_class_name>.h"
#include "examples/helloworldcostfunction.h"

 private:
  double target_value_;
};

}  // namespace helloworld