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

55 lines
1.6 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_REPDIAG_H
#define IGL_REPDIAG_H
#include "igl_inline.h"
#define EIGEN_YES_I_KNOW_SPARSE_MODULE_IS_NOT_STABLE_YET
#include <Eigen/Dense>
#include <Eigen/Sparse>
namespace igl
{
// REPDIAG repeat a matrix along the diagonal a certain number of times, so
// that if A is a m by n matrix and we want to repeat along the diagonal d
// times, we get a m*d by n*d matrix B such that:
// B( (k*m+1):(k*m+1+m-1), (k*n+1):(k*n+1+n-1)) = A
// for k from 0 to d-1
//
// Inputs:
// A m by n matrix we are repeating along the diagonal. May be dense or
// sparse
// d number of times to repeat A along the diagonal
// Outputs:
// B m*d by n*d matrix with A repeated d times along the diagonal,
// will be dense or sparse to match A
//
// Sparse version
template <typename T>
IGL_INLINE void repdiag(
const Eigen::SparseMatrix<T>& A,
const int d,
Eigen::SparseMatrix<T>& B);
// Dense version
template <typename T>
IGL_INLINE void repdiag(
const Eigen::Matrix<T,Eigen::Dynamic,Eigen::Dynamic> & A,
const int d,
Eigen::Matrix<T,Eigen::Dynamic,Eigen::Dynamic> & B);
// Wrapper with B as output
template <class Mat>
IGL_INLINE Mat repdiag(const Mat & A, const int d);
}
#ifndef IGL_STATIC_LIBRARY
# include "repdiag.cpp"
#endif
#endif