软件简介

Tapkee 是一个 C++ 模版库，提供了降维操作功能。The Tapkee origins from the code developed during
GSoC 2011 as
the part of the Shogun machine learning toolbox. The project aim is to provide efficient and flexible
standalone library for dimensionality reduction which can be easily integrated
to existing codebases. Tapkee leverages capabilities of effective Eigen3
linear algebra library and optionally makes use
of the ARPACK eigensolver. The
library uses CoverTree and VP-tree data structures to compute nearest
neighbors. To achieve greater flexibility we provide a callback interface
which decouples dimension reduction algorithms from the data representation
and storage schemes.

一个最简单的示例：

#include <tapkee/tapkee.hpp>
#include <tapkee/callbacks/dummy_callbacks.hpp>

using namespace std;
using namespace tapkee;

struct MyDistanceCallback
{
  ScalarType distance(IndexType l, IndexType r) { return abs(l-r); } 
};

int main(int argc, const char** argv)
{
  const int N = 100;
  vector<IndexType> indices(N);
  for (int i=0; i<N; i++) indices[i] = i;

  MyDistanceCallback d;

  TapkeeOutput output = tapkee::initialize() 
     .withParameters((method=MultidimensionalScaling,target_dimension=1))
     .withDistance(d)
     .embedUsing(indices);

  cout << output.embedding.transpose() << endl;
  return 0;
}