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

42 lines
1.3 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_COLUMNIZE_H
#define IGL_COLUMNIZE_H
#include "igl_inline.h"
#include <Eigen/Core>
namespace igl
{
// "Columnize" a stack of block matrices. If A = [A1,A2,A3,...,Ak] with each A*
// an m by n block then this produces the column vector whose entries are
// B(j*m*k+i*k+b) = A(i,b*n+j);
// or if A = [A1;A2;...;Ak] then
// B(j*m*k+i*k+b) = A(i+b*m,j);
//
// Templates:
// T should be a eigen matrix primitive type like int or double
// Inputs:
// A m*k by n (dim: 1) or m by n*k (dim: 2) eigen Matrix of type T values
// k number of blocks
// dim dimension in which blocks are stacked
// Output
// B m*n*k eigen vector of type T values,
//
// See also: transpose_blocks
template <typename DerivedA, typename DerivedB>
IGL_INLINE void columnize(
const Eigen::PlainObjectBase<DerivedA> & A,
const int k,
const int dim,
Eigen::PlainObjectBase<DerivedB> & B);
}
#ifndef IGL_STATIC_LIBRARY
# include "columnize.cpp"
#endif
#endif