densitytreeinternal.cpp

dysii是一款非常出色的滤波函数库

#include "DensityTreeInternal.hpp"

#include "DensityTreeLeaf.hpp"

using namespace indii::ml::aux;

DensityTreeInternal::DensityTreeInternal() : splitIndex(0), splitValue(0.0),
    left(NULL), right(NULL) {
  //
}

DensityTreeInternal::DensityTreeInternal(const vector& lower,
    const vector& upper, const unsigned int splitIndex,
    const double splitValue, DensityTreeNode* left, DensityTreeNode* right) :
    DensityTreeNode(lower, upper, left->getWeight() + right->getWeight(),
        left->getVolume() + right->getVolume()),
    splitIndex(splitIndex), splitValue(splitValue), left(left), right(right) {
  //
}

DensityTreeInternal::DensityTreeInternal(const DensityTreeInternal& o) :
    DensityTreeNode(o), splitIndex(o.splitIndex), splitValue(o.splitValue),
    left(NULL), right(NULL) {
  if (o.left != NULL) {
    if (typeid(*o.left) == typeid(DensityTreeInternal)) {
      left = new DensityTreeInternal(
          static_cast<DensityTreeInternal&>(*o.left));
    } else if (typeid(*o.left) == typeid(DensityTreeLeaf)) {
      left = new DensityTreeLeaf(
          static_cast<DensityTreeLeaf&>(*o.left));
    } else {
      assert(false);
    }
    assert (left != NULL);
  }
  if (o.right != NULL) {
    if (typeid(*o.right) == typeid(DensityTreeInternal)) {
      right = new DensityTreeInternal(
          static_cast<DensityTreeInternal&>(*o.right));
    } else if (typeid(*o.right) == typeid(DensityTreeLeaf)) {
      right = new DensityTreeLeaf(
          static_cast<DensityTreeLeaf&>(*o.right));
    } else {
      assert(false);
    }
    assert (right != NULL);
  }
}

DensityTreeInternal::~DensityTreeInternal() {
  delete left;
  delete right;
}

DensityTreeInternal& DensityTreeInternal::operator=(
    const DensityTreeInternal& o) {
  DensityTreeNode::operator=(o);

  splitIndex = o.splitIndex;
  splitValue = o.splitValue;

  if (o.left != NULL) {
    if (typeid(*o.left) == typeid(DensityTreeInternal)) {
      left = new DensityTreeInternal(
          static_cast<DensityTreeInternal&>(*o.left));
    } else if (typeid(*o.left) == typeid(DensityTreeLeaf)) {
      left = new DensityTreeLeaf(
          static_cast<DensityTreeLeaf&>(*o.left));
    } else {
      assert(false);
    }
    assert (left != NULL);
  }
  if (o.right != NULL) {
    if (typeid(*o.right) == typeid(DensityTreeInternal)) {
      right = new DensityTreeInternal(
          static_cast<DensityTreeInternal&>(*o.right));
    } else if (typeid(*o.right) == typeid(DensityTreeLeaf)) {
      right = new DensityTreeLeaf(
          static_cast<DensityTreeLeaf&>(*o.right));
    } else {
      assert(false);
    }
    assert (right != NULL);
  }
  
  return *this;
}

vector DensityTreeInternal::sumExpectation() {
  return left->sumExpectation() + right->sumExpectation();
}

symmetric_matrix DensityTreeInternal::sumCovariance() {
  return left->sumCovariance() + right->sumCovariance();
}

vector DensityTreeInternal::sample(const double u) {
  /* pre-condition */
  assert (u >= 0.0 && u <= getWeight());

  if (u <= left->getWeight()) {
    return left->sample(u);
  } else {
    return right->sample(u - left->getWeight());
  }
}

double DensityTreeInternal::densityAt(const vector& x) {
  /* pre-condition */
  assert (x.size() == getLower().size());
  
  if (x(splitIndex) < splitValue) {
    return left->densityAt(x);
  } else {
    return right->densityAt(x);
  }
}