internal/ceres/parallel_for.cc

// Ceres Solver - A fast non-linear least squares minimizer
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// http://ceres-solver.org/
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// Author: vitus@google.com (Michael Vitus)

#include "ceres/parallel_for.h"

#include <algorithm>
#include <atomic>
#include <cmath>
#include <condition_variable>
#include <memory>
#include <mutex>
#include <tuple>

#include "ceres/internal/config.h"
#include "ceres/parallel_vector_ops.h"
#include "glog/logging.h"

namespace ceres::internal {

int MaxNumThreadsAvailable() { return ThreadPool::MaxNumThreadsAvailable(); }

void ParallelSetZero(ContextImpl* context,
                     int num_threads,
                     double* values,
                     int num_values) {
  ParallelFor(context,
              0,
              num_values,
              num_threads,
              [values](std::tuple<int, int> range) {
                auto [start, end] = range;
                std::fill(values + start, values + end, 0.);
              });
}

}  // namespace ceres::internal