Files
secondo/Algebras/ImageSimilarity/dataset.cpp
2026-01-23 17:03:45 +08:00

114 lines
2.7 KiB
C++

/*
----
This file is NOT part of SECONDO.
Authors: Greg Hamerly and Jonathan Drake
Feedback: hamerly@cs.baylor.edu
See: http://cs.baylor.edu/~hamerly/software/kmeans.php
Copyright 2014
----
//paragraph [1] Title: [{\Large \bf \begin{center}] [\end{center}}]
//[TOC] [\tableofcontents]
[1] Implementation of the dataset
1 Implementation of the dataset
*/
/* Authors: Greg Hamerly and Jonathan Drake
* Feedback: hamerly@cs.baylor.edu
* See: http://cs.baylor.edu/~hamerly/software/kmeans.php
* Copyright 2014
*/
#include "dataset.h"
#include <iostream>
#include <iomanip>
#include <cassert>
#include <cstring>
// print the dataset to standard output (cout), using formatting to keep the
// data in matrix format
void Dataset::print() const {
std::ostream &out = std::cout;
out.precision(6);
int ndx = 0;
for (int i = 0; i < n; ++i) {
for (int j = 0; j < d; ++j) {
out << std::setw(13) << data[ndx++] << " ";
}
out << std::endl;
}
}
// returns a (modifiable) reference to the value in dimension "dim" from record
// "ndx"
double &Dataset::operator()(int ndx, int dim) {
# ifdef DEBUG
assert(ndx < n);
assert(dim < d);
# endif
return data[ndx * d + dim];
}
// returns a (const) reference to the value in dimension "dim" from record "ndx"
const double &Dataset::operator()(int ndx, int dim) const {
# ifdef DEBUG
assert(ndx < n);
assert(dim < d);
# endif
return data[ndx * d + dim];
}
// fill the entire dataset with value. Does NOT update sumDataSquared.
void Dataset::fill(double value) {
for (int i = 0; i < nd; ++i) {
data[i] = value;
}
}
// copy constructor -- makes a deep copy of everything in x
Dataset::Dataset(Dataset const &x) {
n = d = nd = 0;
data = sumDataSquared = NULL;
*this = x;
}
// operator= is the standard deep-copy assignment operator, which
// returns a const reference to *this.
Dataset const &Dataset::operator=(Dataset const &x) {
if (this != &x) {
// reallocate sumDataSquared and data as necessary
if (n != x.n) {
delete [] sumDataSquared;
sumDataSquared = x.sumDataSquared ? new double[x.n] : NULL;
}
if (nd != x.nd) {
delete [] data;
data = x.data ? new double[x.nd] : NULL;
}
// reflect the new sizes
n = x.n;
d = x.d;
nd = x.nd;
// copy data as appropriate
if (x.sumDataSquared) {
memcpy(sumDataSquared, x.sumDataSquared, x.n * sizeof(double));
}
if (x.data) {
memcpy(data, x.data, x.nd * sizeof(double));
}
}
// return a reference for chaining assignments
return *this;
}