You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

91 lines
3.3 KiB

// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2013 Alec Jacobson <alecjacobson@gmail.com>
//
// This Source Code Form is subject to the terms of the Mozilla Public License
// v. 2.0. If a copy of the MPL was not distributed with this file, You can
// obtain one at http://mozilla.org/MPL/2.0/.
#ifndef IGL_SORT_H
#define IGL_SORT_H
#include "igl_inline.h"
#include <vector>
#include <Eigen/Core>
namespace igl
{
/// Sort the elements of a matrix X along a given dimension like matlabs sort
/// function
///
/// @tparam DerivedX derived scalar type, e.g. MatrixXi or MatrixXd
/// @tparam DerivedIX derived integer type, e.g. MatrixXi
/// @param[in] X m by n matrix whose entries are to be sorted
/// @param[in] dim dimensional along which to sort:
/// 1 sort each column (matlab default)
/// 2 sort each row
/// @param[in] ascending sort ascending (true, matlab default) or descending (false)
/// @param[out] Y m by n matrix whose entries are sorted
/// @param[out] IX m by n matrix of indices so that if dim = 1, then in matlab notation
/// for j = 1:n, Y(:,j) = X(I(:,j),j); end
template <typename DerivedX, typename DerivedY, typename DerivedIX>
IGL_INLINE void sort(
const Eigen::DenseBase<DerivedX>& X,
const int dim,
const bool ascending,
Eigen::PlainObjectBase<DerivedY>& Y,
Eigen::PlainObjectBase<DerivedIX>& IX);
/// \overload
template <typename DerivedX, typename DerivedY>
IGL_INLINE void sort(
const Eigen::DenseBase<DerivedX>& X,
const int dim,
const bool ascending,
Eigen::PlainObjectBase<DerivedY>& Y);
/// \overload
///
/// \note This should be renamed to something like sort_small because it is
/// only faster if size(X,dim) is small.
template <typename DerivedX, typename DerivedY, typename DerivedIX>
IGL_INLINE void sort_new(
const Eigen::DenseBase<DerivedX>& X,
const int dim,
const bool ascending,
Eigen::PlainObjectBase<DerivedY>& Y,
Eigen::PlainObjectBase<DerivedIX>& IX);
/// \overload
/// \brief Special case if size(X,dim) == 2
template <typename DerivedX, typename DerivedY, typename DerivedIX>
IGL_INLINE void sort2(
const Eigen::DenseBase<DerivedX>& X,
const int dim,
const bool ascending,
Eigen::PlainObjectBase<DerivedY>& Y,
Eigen::PlainObjectBase<DerivedIX>& IX);
/// \overload
/// \brief Special case if size(X,dim) == 3
template <typename DerivedX, typename DerivedY, typename DerivedIX>
IGL_INLINE void sort3(
const Eigen::DenseBase<DerivedX>& X,
const int dim,
const bool ascending,
Eigen::PlainObjectBase<DerivedY>& Y,
Eigen::PlainObjectBase<DerivedIX>& IX);
/// Act like matlab's [Y,I] = SORT(X) for std library vectors
/// @tparam T should be a class that implements the '<' comparator operator
/// @param[in] unsorted unsorted vector
/// @param[in] ascending sort ascending (true, matlab default) or descending (false)
/// @param[out] sorted sorted vector, allowed to be same as unsorted
/// @param[out] index_map an index map such that sorted[i] = unsorted[index_map[i]]
template <class T>
IGL_INLINE void sort(
const std::vector<T> &unsorted,
const bool ascending,
std::vector<T> &sorted,
std::vector<size_t> &index_map);
}
#ifndef IGL_STATIC_LIBRARY
# include "sort.cpp"
#endif
#endif