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//! includes, system
#include <cmath>
#include <iostream>
#include <iomanip>
#include <vector>
#include <cassert>
#include <fstream>
#include <algorithm>
#include <map>

// includes, projcet
#include "matlab.h"

// namespace, unnamed
namespace {}  // end namespace, unnamed

///////////////////////////////////////////////////////////////////////////////
//! Write a tridiagonal, symmetric matrix in vector representation and
//! it's eigenvalues
//! @param  filename  name of output file
//! @param  d  diagonal entries of the matrix
//! @param  s  superdiagonal entries of the matrix (len = n - 1)
//! @param  eigenvals  eigenvalues of the matrix
//! @param  indices  vector of len n containing the position of the eigenvalues
//!                  if these are sorted in ascending order
//! @param  n  size of the matrix
///////////////////////////////////////////////////////////////////////////////
void writeTridiagSymMatlab(const char *filename, float *d, float *s,
                           float *eigenvals, const unsigned int n) {
  std::ofstream file(filename, std::ios::out);

  // write diagonal entries
  writeVectorMatlab(file, "d", d, n);

  // write superdiagonal entries
  writeVectorMatlab(file, "s", s, n - 1);

  // write eigenvalues
  writeVectorMatlab(file, "eigvals", eigenvals, n);

  file.close();
}