dust3d/third_party/libigl/include/igl/sparse.h

79 lines
2.5 KiB
C++

// 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_SPARSE_H
#define IGL_SPARSE_H
#include "igl_inline.h"
#define EIGEN_YES_I_KNOW_SPARSE_MODULE_IS_NOT_STABLE_YET
#include <Eigen/Dense>
#include <Eigen/Sparse>
namespace igl
{
// Build a sparse matrix from list of indices and values (I,J,V), functions
// like the sparse function in matlab
//
// Templates:
// IndexVector list of indices, value should be non-negative and should
// expect to be cast to an index. Must implement operator(i) to retrieve
// ith element
// ValueVector list of values, value should be expect to be cast to type
// T. Must implement operator(i) to retrieve ith element
// T should be a eigen sparse matrix primitive type like int or double
// Input:
// I nnz vector of row indices of non zeros entries in X
// J nnz vector of column indices of non zeros entries in X
// V nnz vector of non-zeros entries in X
// Optional:
// m number of rows
// n number of cols
// Outputs:
// X m by n matrix of type T whose entries are to be found
//
template <class IndexVector, class ValueVector, typename T>
IGL_INLINE void sparse(
const IndexVector & I,
const IndexVector & J,
const ValueVector & V,
Eigen::SparseMatrix<T>& X);
template <
class IndexVectorI,
class IndexVectorJ,
class ValueVector,
typename T>
IGL_INLINE void sparse(
const IndexVectorI & I,
const IndexVectorJ & J,
const ValueVector & V,
const size_t m,
const size_t n,
Eigen::SparseMatrix<T>& X);
// THIS MAY BE SUPERSEDED BY EIGEN'S .sparseView Indeed it is.
// Convert a full, dense matrix to a sparse one
//
// Templates:
// T should be a eigen sparse matrix primitive type like int or double
// Input:
// D m by n full, dense matrix
// Output:
// X m by n sparse matrix
template <typename DerivedD, typename T>
IGL_INLINE void sparse(
const Eigen::PlainObjectBase<DerivedD>& D,
Eigen::SparseMatrix<T>& X);
// Wrapper with return
template <typename DerivedD>
IGL_INLINE Eigen::SparseMatrix<typename DerivedD::Scalar > sparse(
const Eigen::PlainObjectBase<DerivedD>& D);
}
#ifndef IGL_STATIC_LIBRARY
# include "sparse.cpp"
#endif
#endif