question about selecting landmark points by MaxMin

[weigcdsb]

Hello, I'm kind of confused by the landmark points selction. It seems the strategy is not exactly as the original MaxMin? It's kind of like the "MinSum" strategy? (testdists += pD(testpt,targetpt);) Or could you explain why it's equivalent to MaxMin?

Thanks a lot!

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int aux_landmarkMaxMin(arma::mat& pD, arma::vec& plandmark, arma::vec& seqnp){
  // 4-1. basic setting
  const int nlandmark = plandmark.n_elem;
  const int ntestpts  = seqnp.n_elem;

  // 4-2. we should be careful ; -1 for both vectors
  vec veclandmark = plandmark - 1;
  vec vecseqnp    = seqnp - 1;

  // 4-3. main iteration
  int currentidx      = 0;
  double currentdists = 123456789;
  for (int i=0;i<ntestpts;i++){
    int testpt       = vecseqnp(i);
    double testdists = 0;
    for (int j=0;j<nlandmark;j++){
      int targetpt = veclandmark(j);
      testdists += pD(testpt,targetpt);
    }
    if (testdists<currentdists){
      currentidx   = testpt;
      currentdists = testdists;
    }
  }
  currentidx += 1;

  // 4-4. return output
  return(currentidx);
}

[weigcdsb]

OK, a follow up... I implement the original MaxMin method by myself and fix the starting points, the results are different... These 2 methods are different, would you mind explaining why you choose select landmark by this rather using original MaxMin strategy?