eigen/Eigen/src/Sparse/SparseVector.h
2009-01-15 14:16:41 +00:00

332 lines
10 KiB
C++

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra. Eigen itself is part of the KDE project.
//
// Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr>
//
// Eigen is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 3 of the License, or (at your option) any later version.
//
// Alternatively, you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of
// the License, or (at your option) any later version.
//
// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License and a copy of the GNU General Public License along with
// Eigen. If not, see <http://www.gnu.org/licenses/>.
#ifndef EIGEN_SPARSEVECTOR_H
#define EIGEN_SPARSEVECTOR_H
/** \class SparseVector
*
* \brief a sparse vector class
*
* \param _Scalar the scalar type, i.e. the type of the coefficients
*
* See http://www.netlib.org/linalg/html_templates/node91.html for details on the storage scheme.
*
*/
template<typename _Scalar, int _Flags>
struct ei_traits<SparseVector<_Scalar, _Flags> >
{
typedef _Scalar Scalar;
enum {
IsColVector = _Flags & RowMajorBit ? 0 : 1,
RowsAtCompileTime = IsColVector ? Dynamic : 1,
ColsAtCompileTime = IsColVector ? 1 : Dynamic,
MaxRowsAtCompileTime = RowsAtCompileTime,
MaxColsAtCompileTime = ColsAtCompileTime,
Flags = SparseBit | _Flags,
CoeffReadCost = NumTraits<Scalar>::ReadCost,
SupportedAccessPatterns = FullyCoherentAccessPattern
};
};
template<typename _Scalar, int _Flags>
class SparseVector
: public SparseMatrixBase<SparseVector<_Scalar, _Flags> >
{
public:
EIGEN_SPARSE_GENERIC_PUBLIC_INTERFACE(SparseVector)
protected:
public:
typedef SparseMatrixBase<SparseVector> SparseBase;
enum { IsColVector = ei_traits<SparseVector>::IsColVector };
CompressedStorage<Scalar> m_data;
int m_size;
public:
inline int rows() const { return IsColVector ? m_size : 1; }
inline int cols() const { return IsColVector ? 1 : m_size; }
inline int innerSize() const { return m_size; }
inline int outerSize() const { return 1; }
inline int innerNonZeros(int j) const { ei_assert(j==0); return m_size; }
inline const Scalar* _valuePtr() const { return &m_data.value(0); }
inline Scalar* _valuePtr() { return &m_data.value(0); }
inline const int* _innerIndexPtr() const { return &m_data.index(0); }
inline int* _innerIndexPtr() { return &m_data.index(0); }
inline Scalar coeff(int row, int col) const
{
ei_assert((IsColVector ? col : row)==0);
return coeff(IsColVector ? row : col);
}
inline Scalar coeff(int i) const
{
int start = 0;
int end = m_data.size();
if (start==end)
return Scalar(0);
else if (end>0 && i==m_data.index(end-1))
return m_data.value(end-1);
// ^^ optimization: let's first check if it is the last coefficient
// (very common in high level algorithms)
// TODO move this search to ScalarArray
const int* r = std::lower_bound(&m_data.index(start),&m_data.index(end-1),i);
const int id = r-&m_data.index(0);
return ((*r==i) && (id<end)) ? m_data.value(id) : Scalar(0);
}
inline Scalar& coeffRef(int row, int col)
{
ei_assert((IsColVector ? col : row)==0);
return coeff(IsColVector ? row : col);
}
inline Scalar& coeffRef(int i)
{
int start = 0;
int end = m_data.size();
ei_assert(end>=start && "you probably called coeffRef on a non finalized vector");
ei_assert(end>start && "coeffRef cannot be called on a zero coefficient");
int* r = std::lower_bound(&m_data.index(start),&m_data.index(end),i);
const int id = r-&m_data.index(0);
ei_assert((*r==i) && (id<end) && "coeffRef cannot be called on a zero coefficient");
return m_data.value(id);
}
public:
class InnerIterator;
inline void setZero() { m_data.clear(); }
/** \returns the number of non zero coefficients */
inline int nonZeros() const { return m_data.size(); }
/**
*/
inline void reserve(int reserveSize) { m_data.reserve(reserveSize); }
/**
*/
inline Scalar& fill(int i)
{
m_data.append(0, i);
return m_data.value(m_data.size()-1);
}
/** Like fill() but with random coordinates.
*/
inline Scalar& fillrand(int i)
{
int startId = 0;
int id = m_data.size() - 1;
m_data.resize(id+2);
while ( (id >= startId) && (m_data.index(id) > i) )
{
m_data.index(id+1) = m_data.index(id);
m_data.value(id+1) = m_data.value(id);
--id;
}
m_data.index(id+1) = i;
m_data.value(id+1) = 0;
return m_data.value(id+1);
}
void resize(int newSize)
{
m_size = newSize;
m_data.clear();
}
void resizeNonZeros(int size) { m_data.resize(size); }
inline SparseVector() : m_size(0) { resize(0, 0); }
inline SparseVector(int size) : m_size(0) { resize(size); }
template<typename OtherDerived>
inline SparseVector(const MatrixBase<OtherDerived>& other)
: m_size(0)
{
*this = other.derived();
}
inline SparseVector(const SparseVector& other)
: m_size(0)
{
*this = other.derived();
}
inline void swap(SparseVector& other)
{
std::swap(m_size, other.m_size);
m_data.swap(other.m_data);
}
inline SparseVector& operator=(const SparseVector& other)
{
if (other.isRValue())
{
swap(other.const_cast_derived());
}
else
{
resize(other.size());
m_data = other.m_data;
}
return *this;
}
// template<typename OtherDerived>
// inline SparseVector& operator=(const MatrixBase<OtherDerived>& other)
// {
// const bool needToTranspose = (Flags & RowMajorBit) != (OtherDerived::Flags & RowMajorBit);
// if (needToTranspose)
// {
// // two passes algorithm:
// // 1 - compute the number of coeffs per dest inner vector
// // 2 - do the actual copy/eval
// // Since each coeff of the rhs has to be evaluated twice, let's evauluate it if needed
// typedef typename ei_nested<OtherDerived,2>::type OtherCopy;
// OtherCopy otherCopy(other.derived());
// typedef typename ei_cleantype<OtherCopy>::type _OtherCopy;
//
// resize(other.rows(), other.cols());
// Eigen::Map<VectorXi>(m_outerIndex,outerSize()).setZero();
// // pass 1
// // FIXME the above copy could be merged with that pass
// for (int j=0; j<otherCopy.outerSize(); ++j)
// for (typename _OtherCopy::InnerIterator it(otherCopy, j); it; ++it)
// ++m_outerIndex[it.index()];
//
// // prefix sum
// int count = 0;
// VectorXi positions(outerSize());
// for (int j=0; j<outerSize(); ++j)
// {
// int tmp = m_outerIndex[j];
// m_outerIndex[j] = count;
// positions[j] = count;
// count += tmp;
// }
// m_outerIndex[outerSize()] = count;
// // alloc
// m_data.resize(count);
// // pass 2
// for (int j=0; j<otherCopy.outerSize(); ++j)
// for (typename _OtherCopy::InnerIterator it(otherCopy, j); it; ++it)
// {
// int pos = positions[it.index()]++;
// m_data.index(pos) = j;
// m_data.value(pos) = it.value();
// }
//
// return *this;
// }
// else
// {
// // there is no special optimization
// return SparseMatrixBase<SparseMatrix>::operator=(other.derived());
// }
// }
friend std::ostream & operator << (std::ostream & s, const SparseVector& m)
{
for (unsigned int i=0; i<m.nonZeros(); ++i)
s << "(" << m.m_data.value(i) << "," << m.m_data.index(i) << ") ";
s << std::endl;
return s;
}
// this specialized version does not seems to be faster
// Scalar dot(const SparseVector& other) const
// {
// int i=0, j=0;
// Scalar res = 0;
// asm("#begindot");
// while (i<nonZeros() && j<other.nonZeros())
// {
// if (m_data.index(i)==other.m_data.index(j))
// {
// res += m_data.value(i) * ei_conj(other.m_data.value(j));
// ++i; ++j;
// }
// else if (m_data.index(i)<other.m_data.index(j))
// ++i;
// else
// ++j;
// }
// asm("#enddot");
// return res;
// }
/** Destructor */
inline ~SparseVector() {}
};
template<typename Scalar, int _Flags>
class SparseVector<Scalar,_Flags>::InnerIterator
{
public:
InnerIterator(const SparseVector& vec, int outer=0)
: m_vector(vec), m_id(0), m_end(vec.nonZeros())
{
ei_assert(outer==0);
}
template<unsigned int Added, unsigned int Removed>
InnerIterator(const Flagged<SparseVector,Added,Removed>& vec, int outer)
: m_vector(vec._expression()), m_id(0), m_end(m_vector.nonZeros())
{}
inline InnerIterator& operator++() { m_id++; return *this; }
inline Scalar value() const { return m_vector.m_data.value(m_id); }
inline Scalar& valueRef() { return const_cast<Scalar&>(m_vector.m_data.value(m_id)); }
inline int index() const { return m_vector.m_data.index(m_id); }
inline int row() const { return IsColVector ? index() : 0; }
inline int col() const { return IsColVector ? 0 : index(); }
inline operator bool() const { return (m_id < m_end); }
protected:
const SparseVector& m_vector;
int m_id;
const int m_end;
};
#endif // EIGEN_SPARSEVECTOR_H