49 lines
1.4 KiB
C++
49 lines
1.4 KiB
C++
#include "find_zero.h"
|
|
#include "for_each.h"
|
|
#include "any.h"
|
|
|
|
template <typename AType, typename DerivedI>
|
|
IGL_INLINE void igl::find_zero(
|
|
const Eigen::SparseMatrix<AType> & A,
|
|
const int dim,
|
|
Eigen::PlainObjectBase<DerivedI> & I)
|
|
{
|
|
assert((dim == 1 || dim == 2) && "dim must be 2 or 1");
|
|
// Get size of input
|
|
int m = A.rows();
|
|
int n = A.cols();
|
|
// I starts by containing guess where 0 might be
|
|
I = DerivedI::Zero(dim==1?n:m);
|
|
Eigen::Array<bool,Eigen::Dynamic,1> found =
|
|
Eigen::Array<bool,Eigen::Dynamic,1>::Zero(dim==1?n:m);
|
|
const auto func = [&I,&found,&dim](int i, int j, const int v)
|
|
{
|
|
if(dim == 2)
|
|
{
|
|
std::swap(i,j);
|
|
}
|
|
// Coded as if dim == 1, assuming swap for dim == 2
|
|
// Have we already found a zero?
|
|
if(!found(j))
|
|
{
|
|
if(I(j) != i || v == 0)
|
|
{
|
|
// either there was an implicit zero between the last element and this
|
|
// one, or this one is zero
|
|
found(j) = true;
|
|
}else
|
|
{
|
|
// If not found, then guess that next element will be zero
|
|
I(j) = I(j)+1;
|
|
}
|
|
}
|
|
};
|
|
for_each(A,func);
|
|
}
|
|
|
|
#ifdef IGL_STATIC_LIBRARY
|
|
// Explicit template instantiation
|
|
// generated by autoexplicit.sh
|
|
template void igl::find_zero<bool, Eigen::Matrix<int, -1, 1, 0, -1, 1> >(Eigen::SparseMatrix<bool, 0, int> const&, int, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, 1, 0, -1, 1> >&);
|
|
#endif
|