internal/ceres/solver_utils.h

// Ceres Solver - A fast non-linear least squares minimizer
// Copyright 2023 Google Inc. All rights reserved.
// http://ceres-solver.org/
//
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// modification, are permitted provided that the following conditions are met:
//
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//   this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
//   this list of conditions and the following disclaimer in the documentation
//   and/or other materials provided with the distribution.
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//
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// Author: sameeragarwal@google.com (Sameer Agarwal)

#ifndef CERES_INTERNAL_SOLVER_UTILS_H_
#define CERES_INTERNAL_SOLVER_UTILS_H_

#include <algorithm>
#include <string_view>

#include "ceres/internal/disable_warnings.h"
#include "ceres/internal/export.h"
#include "ceres/iteration_callback.h"
#include "ceres/types.h"

namespace ceres::internal {

template <typename SummaryType>
bool IsSolutionUsable(const SummaryType& summary) {
  return (summary.termination_type == CONVERGENCE ||
          summary.termination_type == NO_CONVERGENCE ||
          summary.termination_type == USER_SUCCESS);
}

template <typename SummaryType>
void SetSummaryFinalCost(SummaryType* summary) {
  summary->final_cost = summary->initial_cost;
  // We need the loop here, instead of just looking at the last
  // iteration because the minimizer maybe making non-monotonic steps.
  for (int i = 0; i < summary->iterations.size(); ++i) {
    const IterationSummary& iteration_summary = summary->iterations[i];
    summary->final_cost = std::min(iteration_summary.cost, summary->final_cost);
  }
}

CERES_NO_EXPORT
std::string_view VersionString() noexcept;

}  // namespace ceres::internal

#include "ceres/internal/reenable_warnings.h"

#endif  // CERES_INTERNAL_SOLVER_UTILS_H_