447 lines
16 KiB
Text
447 lines
16 KiB
Text
|
//----------------------------------------------------------------------
|
||
|
|
// File: kd_dump.cc
|
||
|
|
// Programmer: David Mount
|
||
|
|
// Description: Dump and Load for kd- and bd-trees
|
||
|
|
// Last modified: 01/04/05 (Version 1.0)
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
// Copyright (c) 1997-2005 University of Maryland and Sunil Arya and
|
||
|
|
// David Mount. All Rights Reserved.
|
||
|
|
//
|
||
|
|
// This software and related documentation is part of the Approximate
|
||
|
|
// Nearest Neighbor Library (ANN). This software is provided under
|
||
|
|
// the provisions of the Lesser GNU Public License (LGPL). See the
|
||
|
|
// file ../ReadMe.txt for further information.
|
||
|
|
//
|
||
|
|
// The University of Maryland (U.M.) and the authors make no
|
||
|
|
// representations about the suitability or fitness of this software for
|
||
|
|
// any purpose. It is provided "as is" without express or implied
|
||
|
|
// warranty.
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
// History:
|
||
|
|
// Revision 0.1 03/04/98
|
||
|
|
// Initial release
|
||
|
|
// Revision 1.0 04/01/05
|
||
|
|
// Moved dump out of kd_tree.cc into this file.
|
||
|
|
// Added kd-tree load constructor.
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
// This file contains routines for dumping kd-trees and bd-trees and
|
||
|
|
// reloading them. (It is an abuse of policy to include both kd- and
|
||
|
|
// bd-tree routines in the same file, sorry. There should be no problem
|
||
|
|
// in deleting the bd- versions of the routines if they are not
|
||
|
|
// desired.)
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
|
||
|
|
#include <string.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include "kd_tree.h" // kd-tree declarations
|
||
|
|
#include "bd_tree.h" // bd-tree declarations
|
||
|
|
|
||
|
|
using namespace std; // make std:: available
|
||
|
|
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
// Constants
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
|
||
|
|
const int STRING_LEN = 500; // maximum string length
|
||
|
|
const double EPSILON = 1E-5; // small number for float comparison
|
||
|
|
|
||
|
|
enum ANNtreeType {KD_TREE, BD_TREE}; // tree types (used in loading)
|
||
|
|
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
// Procedure declarations
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
|
||
|
|
static ANNkd_ptr annReadDump( // read dump file
|
||
|
|
istream &in, // input stream
|
||
|
|
ANNtreeType tree_type, // type of tree expected
|
||
|
|
ANNpointArray &the_pts, // new points (if applic)
|
||
|
|
ANNidxArray &the_pidx, // point indices (returned)
|
||
|
|
int &the_dim, // dimension (returned)
|
||
|
|
int &the_n_pts, // number of points (returned)
|
||
|
|
int &the_bkt_size, // bucket size (returned)
|
||
|
|
ANNpoint &the_bnd_box_lo, // low bounding point
|
||
|
|
ANNpoint &the_bnd_box_hi); // high bounding point
|
||
|
|
|
||
|
|
static ANNkd_ptr annReadTree( // read tree-part of dump file
|
||
|
|
istream &in, // input stream
|
||
|
|
ANNtreeType tree_type, // type of tree expected
|
||
|
|
ANNidxArray the_pidx, // point indices (modified)
|
||
|
|
int &next_idx); // next index (modified)
|
||
|
|
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
// ANN kd- and bd-tree Dump Format
|
||
|
|
// The dump file begins with a header containing the version of
|
||
|
|
// ANN, an optional section containing the points, followed by
|
||
|
|
// a description of the tree. The tree is printed in preorder.
|
||
|
|
//
|
||
|
|
// Format:
|
||
|
|
// #ANN <version number> <comments> [END_OF_LINE]
|
||
|
|
// points <dim> <n_pts> (point coordinates: this is optional)
|
||
|
|
// 0 <xxx> <xxx> ... <xxx> (point indices and coordinates)
|
||
|
|
// 1 <xxx> <xxx> ... <xxx>
|
||
|
|
// ...
|
||
|
|
// tree <dim> <n_pts> <bkt_size>
|
||
|
|
// <xxx> <xxx> ... <xxx> (lower end of bounding box)
|
||
|
|
// <xxx> <xxx> ... <xxx> (upper end of bounding box)
|
||
|
|
// If the tree is null, then a single line "null" is
|
||
|
|
// output. Otherwise the nodes of the tree are printed
|
||
|
|
// one per line in preorder. Leaves and splitting nodes
|
||
|
|
// have the following formats:
|
||
|
|
// Leaf node:
|
||
|
|
// leaf <n_pts> <bkt[0]> <bkt[1]> ... <bkt[n-1]>
|
||
|
|
// Splitting nodes:
|
||
|
|
// split <cut_dim> <cut_val> <lo_bound> <hi_bound>
|
||
|
|
//
|
||
|
|
// For bd-trees:
|
||
|
|
//
|
||
|
|
// Shrinking nodes:
|
||
|
|
// shrink <n_bnds>
|
||
|
|
// <cut_dim> <cut_val> <side>
|
||
|
|
// <cut_dim> <cut_val> <side>
|
||
|
|
// ... (repeated n_bnds times)
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
|
||
|
|
void ANNkd_tree::Dump( // dump entire tree
|
||
|
|
ANNbool with_pts, // print points as well?
|
||
|
|
ostream &out) // output stream
|
||
|
|
{
|
||
|
|
out << "#ANN " << ANNversion << "\n";
|
||
|
|
out.precision(ANNcoordPrec); // use full precision in dumping
|
||
|
|
if (with_pts) { // print point coordinates
|
||
|
|
out << "points " << dim << " " << n_pts << "\n";
|
||
|
|
for (int i = 0; i < n_pts; i++) {
|
||
|
|
out << i << " ";
|
||
|
|
annPrintPt(pts[i], dim, out);
|
||
|
|
out << "\n";
|
||
|
|
}
|
||
|
|
}
|
||
|
|
out << "tree " // print tree elements
|
||
|
|
<< dim << " "
|
||
|
|
<< n_pts << " "
|
||
|
|
<< bkt_size << "\n";
|
||
|
|
|
||
|
|
annPrintPt(bnd_box_lo, dim, out); // print lower bound
|
||
|
|
out << "\n";
|
||
|
|
annPrintPt(bnd_box_hi, dim, out); // print upper bound
|
||
|
|
out << "\n";
|
||
|
|
|
||
|
|
if (root == NULL) // empty tree?
|
||
|
|
out << "null\n";
|
||
|
|
else {
|
||
|
|
root->dump(out); // invoke printing at root
|
||
|
|
}
|
||
|
|
out.precision(0); // restore default precision
|
||
|
|
}
|
||
|
|
|
||
|
|
void ANNkd_split::dump( // dump a splitting node
|
||
|
|
ostream &out) // output stream
|
||
|
|
{
|
||
|
|
out << "split " << cut_dim << " " << cut_val << " ";
|
||
|
|
out << cd_bnds[ANN_LO] << " " << cd_bnds[ANN_HI] << "\n";
|
||
|
|
|
||
|
|
child[ANN_LO]->dump(out); // print low child
|
||
|
|
child[ANN_HI]->dump(out); // print high child
|
||
|
|
}
|
||
|
|
|
||
|
|
void ANNkd_leaf::dump( // dump a leaf node
|
||
|
|
ostream &out) // output stream
|
||
|
|
{
|
||
|
|
if (this == KD_TRIVIAL) { // canonical trivial leaf node
|
||
|
|
out << "leaf 0\n"; // leaf no points
|
||
|
|
}
|
||
|
|
else{
|
||
|
|
out << "leaf " << n_pts;
|
||
|
|
for (int j = 0; j < n_pts; j++) {
|
||
|
|
out << " " << bkt[j];
|
||
|
|
}
|
||
|
|
out << "\n";
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void ANNbd_shrink::dump( // dump a shrinking node
|
||
|
|
ostream &out) // output stream
|
||
|
|
{
|
||
|
|
out << "shrink " << n_bnds << "\n";
|
||
|
|
for (int j = 0; j < n_bnds; j++) {
|
||
|
|
out << bnds[j].cd << " " << bnds[j].cv << " " << bnds[j].sd << "\n";
|
||
|
|
}
|
||
|
|
child[ANN_IN]->dump(out); // print in-child
|
||
|
|
child[ANN_OUT]->dump(out); // print out-child
|
||
|
|
}
|
||
|
|
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
// Load kd-tree from dump file
|
||
|
|
// This rebuilds a kd-tree which was dumped to a file. The dump
|
||
|
|
// file contains all the basic tree information according to a
|
||
|
|
// preorder traversal. We assume that the dump file also contains
|
||
|
|
// point data. (This is to guarantee the consistency of the tree.)
|
||
|
|
// If not, then an error is generated.
|
||
|
|
//
|
||
|
|
// Indirectly, this procedure allocates space for points, point
|
||
|
|
// indices, all nodes in the tree, and the bounding box for the
|
||
|
|
// tree. When the tree is destroyed, all but the points are
|
||
|
|
// deallocated.
|
||
|
|
//
|
||
|
|
// This routine calls annReadDump to do all the work.
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
|
||
|
|
ANNkd_tree::ANNkd_tree( // build from dump file
|
||
|
|
istream &in) // input stream for dump file
|
||
|
|
{
|
||
|
|
int the_dim; // local dimension
|
||
|
|
int the_n_pts; // local number of points
|
||
|
|
int the_bkt_size; // local number of points
|
||
|
|
ANNpoint the_bnd_box_lo; // low bounding point
|
||
|
|
ANNpoint the_bnd_box_hi; // high bounding point
|
||
|
|
ANNpointArray the_pts; // point storage
|
||
|
|
ANNidxArray the_pidx; // point index storage
|
||
|
|
ANNkd_ptr the_root; // root of the tree
|
||
|
|
|
||
|
|
the_root = annReadDump( // read the dump file
|
||
|
|
in, // input stream
|
||
|
|
KD_TREE, // expecting a kd-tree
|
||
|
|
the_pts, // point array (returned)
|
||
|
|
the_pidx, // point indices (returned)
|
||
|
|
the_dim, the_n_pts, the_bkt_size, // basic tree info (returned)
|
||
|
|
the_bnd_box_lo, the_bnd_box_hi); // bounding box info (returned)
|
||
|
|
|
||
|
|
// create a skeletal tree
|
||
|
|
SkeletonTree(the_n_pts, the_dim, the_bkt_size, the_pts, the_pidx);
|
||
|
|
|
||
|
|
bnd_box_lo = the_bnd_box_lo;
|
||
|
|
bnd_box_hi = the_bnd_box_hi;
|
||
|
|
|
||
|
|
root = the_root; // set the root
|
||
|
|
}
|
||
|
|
|
||
|
|
ANNbd_tree::ANNbd_tree( // build bd-tree from dump file
|
||
|
|
istream &in) : ANNkd_tree() // input stream for dump file
|
||
|
|
{
|
||
|
|
int the_dim; // local dimension
|
||
|
|
int the_n_pts; // local number of points
|
||
|
|
int the_bkt_size; // local number of points
|
||
|
|
ANNpoint the_bnd_box_lo; // low bounding point
|
||
|
|
ANNpoint the_bnd_box_hi; // high bounding point
|
||
|
|
ANNpointArray the_pts; // point storage
|
||
|
|
ANNidxArray the_pidx; // point index storage
|
||
|
|
ANNkd_ptr the_root; // root of the tree
|
||
|
|
|
||
|
|
the_root = annReadDump( // read the dump file
|
||
|
|
in, // input stream
|
||
|
|
BD_TREE, // expecting a bd-tree
|
||
|
|
the_pts, // point array (returned)
|
||
|
|
the_pidx, // point indices (returned)
|
||
|
|
the_dim, the_n_pts, the_bkt_size, // basic tree info (returned)
|
||
|
|
the_bnd_box_lo, the_bnd_box_hi); // bounding box info (returned)
|
||
|
|
|
||
|
|
// create a skeletal tree
|
||
|
|
SkeletonTree(the_n_pts, the_dim, the_bkt_size, the_pts, the_pidx);
|
||
|
|
bnd_box_lo = the_bnd_box_lo;
|
||
|
|
bnd_box_hi = the_bnd_box_hi;
|
||
|
|
|
||
|
|
root = the_root; // set the root
|
||
|
|
}
|
||
|
|
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
// annReadDump - read a dump file
|
||
|
|
//
|
||
|
|
// This procedure reads a dump file, constructs a kd-tree
|
||
|
|
// and returns all the essential information needed to actually
|
||
|
|
// construct the tree. Because this procedure is used for
|
||
|
|
// constructing both kd-trees and bd-trees, the second argument
|
||
|
|
// is used to indicate which type of tree we are expecting.
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
|
||
|
|
static ANNkd_ptr annReadDump(
|
||
|
|
istream &in, // input stream
|
||
|
|
ANNtreeType tree_type, // type of tree expected
|
||
|
|
ANNpointArray &the_pts, // new points (returned)
|
||
|
|
ANNidxArray &the_pidx, // point indices (returned)
|
||
|
|
int &the_dim, // dimension (returned)
|
||
|
|
int &the_n_pts, // number of points (returned)
|
||
|
|
int &the_bkt_size, // bucket size (returned)
|
||
|
|
ANNpoint &the_bnd_box_lo, // low bounding point (ret'd)
|
||
|
|
ANNpoint &the_bnd_box_hi) // high bounding point (ret'd)
|
||
|
|
{
|
||
|
|
int j;
|
||
|
|
char str[STRING_LEN]; // storage for string
|
||
|
|
char version[STRING_LEN]; // ANN version number
|
||
|
|
ANNkd_ptr the_root = NULL;
|
||
|
|
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
// Input file header
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
in >> str; // input header
|
||
|
|
if (strcmp(str, "#ANN") != 0) { // incorrect header
|
||
|
|
annError("Incorrect header for dump file", ANNabort);
|
||
|
|
}
|
||
|
|
in.getline(version, STRING_LEN); // get version (ignore)
|
||
|
|
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
// Input the points
|
||
|
|
// An array the_pts is allocated and points are read from
|
||
|
|
// the dump file.
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
in >> str; // get major heading
|
||
|
|
if (strcmp(str, "points") == 0) { // points section
|
||
|
|
in >> the_dim; // input dimension
|
||
|
|
in >> the_n_pts; // number of points
|
||
|
|
// allocate point storage
|
||
|
|
the_pts = annAllocPts(the_n_pts, the_dim);
|
||
|
|
for (int i = 0; i < the_n_pts; i++) { // input point coordinates
|
||
|
|
ANNidx idx; // point index
|
||
|
|
in >> idx; // input point index
|
||
|
|
if (idx < 0 || idx >= the_n_pts) {
|
||
|
|
annError("Point index is out of range", ANNabort);
|
||
|
|
}
|
||
|
|
for (j = 0; j < the_dim; j++) {
|
||
|
|
in >> the_pts[idx][j]; // read point coordinates
|
||
|
|
}
|
||
|
|
}
|
||
|
|
in >> str; // get next major heading
|
||
|
|
}
|
||
|
|
else { // no points were input
|
||
|
|
annError("Points must be supplied in the dump file", ANNabort);
|
||
|
|
}
|
||
|
|
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
// Input the tree
|
||
|
|
// After the basic header information, we invoke annReadTree
|
||
|
|
// to do all the heavy work. We create our own array of
|
||
|
|
// point indices (so we can pass them to annReadTree())
|
||
|
|
// but we do not deallocate them. They will be deallocated
|
||
|
|
// when the tree is destroyed.
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
if (strcmp(str, "tree") == 0) { // tree section
|
||
|
|
in >> the_dim; // read dimension
|
||
|
|
in >> the_n_pts; // number of points
|
||
|
|
in >> the_bkt_size; // bucket size
|
||
|
|
the_bnd_box_lo = annAllocPt(the_dim); // allocate bounding box pts
|
||
|
|
the_bnd_box_hi = annAllocPt(the_dim);
|
||
|
|
|
||
|
|
for (j = 0; j < the_dim; j++) { // read bounding box low
|
||
|
|
in >> the_bnd_box_lo[j];
|
||
|
|
}
|
||
|
|
for (j = 0; j < the_dim; j++) { // read bounding box low
|
||
|
|
in >> the_bnd_box_hi[j];
|
||
|
|
}
|
||
|
|
the_pidx = new ANNidx[the_n_pts]; // allocate point index array
|
||
|
|
int next_idx = 0; // number of indices filled
|
||
|
|
// read the tree and indices
|
||
|
|
the_root = annReadTree(in, tree_type, the_pidx, next_idx);
|
||
|
|
if (next_idx != the_n_pts) { // didn't see all the points?
|
||
|
|
annError("Didn't see as many points as expected", ANNwarn);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
annError("Illegal dump format. Expecting section heading", ANNabort);
|
||
|
|
}
|
||
|
|
return the_root;
|
||
|
|
}
|
||
|
|
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
// annReadTree - input tree and return pointer
|
||
|
|
//
|
||
|
|
// annReadTree reads in a node of the tree, makes any recursive
|
||
|
|
// calls as needed to input the children of this node (if internal).
|
||
|
|
// It returns a pointer to the node that was created. An array
|
||
|
|
// of point indices is given along with a pointer to the next
|
||
|
|
// available location in the array. As leaves are read, their
|
||
|
|
// point indices are stored here, and the point buckets point
|
||
|
|
// to the first entry in the array.
|
||
|
|
//
|
||
|
|
// Recall that these are the formats. The tree is given in
|
||
|
|
// preorder.
|
||
|
|
//
|
||
|
|
// Leaf node:
|
||
|
|
// leaf <n_pts> <bkt[0]> <bkt[1]> ... <bkt[n-1]>
|
||
|
|
// Splitting nodes:
|
||
|
|
// split <cut_dim> <cut_val> <lo_bound> <hi_bound>
|
||
|
|
//
|
||
|
|
// For bd-trees:
|
||
|
|
//
|
||
|
|
// Shrinking nodes:
|
||
|
|
// shrink <n_bnds>
|
||
|
|
// <cut_dim> <cut_val> <side>
|
||
|
|
// <cut_dim> <cut_val> <side>
|
||
|
|
// ... (repeated n_bnds times)
|
||
|
|
//----------------------------------------------------------------------
|
||
|
|
|
||
|
|
static ANNkd_ptr annReadTree(
|
||
|
|
istream &in, // input stream
|
||
|
|
ANNtreeType tree_type, // type of tree expected
|
||
|
|
ANNidxArray the_pidx, // point indices (modified)
|
||
|
|
int &next_idx) // next index (modified)
|
||
|
|
{
|
||
|
|
char tag[STRING_LEN]; // tag (leaf, split, shrink)
|
||
|
|
int n_pts; // number of points in leaf
|
||
|
|
int cd; // cut dimension
|
||
|
|
ANNcoord cv; // cut value
|
||
|
|
ANNcoord lb; // low bound
|
||
|
|
ANNcoord hb; // high bound
|
||
|
|
int n_bnds; // number of bounding sides
|
||
|
|
int sd; // which side
|
||
|
|
|
||
|
|
in >> tag; // input node tag
|
||
|
|
|
||
|
|
if (strcmp(tag, "null") == 0) { // null tree
|
||
|
|
return NULL;
|
||
|
|
}
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
// Read a leaf
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
if (strcmp(tag, "leaf") == 0) { // leaf node
|
||
|
|
|
||
|
|
in >> n_pts; // input number of points
|
||
|
|
int old_idx = next_idx; // save next_idx
|
||
|
|
if (n_pts == 0) { // trivial leaf
|
||
|
|
return KD_TRIVIAL;
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
for (int i = 0; i < n_pts; i++) { // input point indices
|
||
|
|
in >> the_pidx[next_idx++]; // store in array of indices
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return new ANNkd_leaf(n_pts, &the_pidx[old_idx]);
|
||
|
|
}
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
// Read a splitting node
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
else if (strcmp(tag, "split") == 0) { // splitting node
|
||
|
|
|
||
|
|
in >> cd >> cv >> lb >> hb;
|
||
|
|
|
||
|
|
// read low and high subtrees
|
||
|
|
ANNkd_ptr lc = annReadTree(in, tree_type, the_pidx, next_idx);
|
||
|
|
ANNkd_ptr hc = annReadTree(in, tree_type, the_pidx, next_idx);
|
||
|
|
// create new node and return
|
||
|
|
return new ANNkd_split(cd, cv, lb, hb, lc, hc);
|
||
|
|
}
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
// Read a shrinking node (bd-tree only)
|
||
|
|
//------------------------------------------------------------------
|
||
|
|
else if (strcmp(tag, "shrink") == 0) { // shrinking node
|
||
|
|
if (tree_type != BD_TREE) {
|
||
|
|
annError("Shrinking node not allowed in kd-tree", ANNabort);
|
||
|
|
}
|
||
|
|
|
||
|
|
in >> n_bnds; // number of bounding sides
|
||
|
|
// allocate bounds array
|
||
|
|
ANNorthHSArray bds = new ANNorthHalfSpace[n_bnds];
|
||
|
|
for (int i = 0; i < n_bnds; i++) {
|
||
|
|
in >> cd >> cv >> sd; // input bounding halfspace
|
||
|
|
// copy to array
|
||
|
|
bds[i] = ANNorthHalfSpace(cd, cv, sd);
|
||
|
|
}
|
||
|
|
// read inner and outer subtrees
|
||
|
|
ANNkd_ptr ic = annReadTree(in, tree_type, the_pidx, next_idx);
|
||
|
|
ANNkd_ptr oc = annReadTree(in, tree_type, the_pidx, next_idx);
|
||
|
|
// create new node and return
|
||
|
|
return new ANNbd_shrink(n_bnds, bds, ic, oc);
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
annError("Illegal node type in dump file", ANNabort);
|
||
|
|
exit(0); // to keep the compiler happy
|
||
|
|
}
|
||
|
|
}
|