62 lines
1.7 KiB
C
62 lines
1.7 KiB
C
|
#ifndef IGL_LINSPACED_H
|
||
|
#define IGL_LINSPACED_H
|
||
|
#include <Eigen/Core>
|
||
|
// This function is not intended to be a permanent function of libigl. Rather
|
||
|
// it is a "drop-in" workaround for documented bug in Eigen:
|
||
|
// http://eigen.tuxfamily.org/bz/show_bug.cgi?id=1383
|
||
|
//
|
||
|
// Replace:
|
||
|
//
|
||
|
// Eigen::VectorXi::LinSpaced(size,low,high);
|
||
|
//
|
||
|
// With:
|
||
|
//
|
||
|
// igl::LinSpaced<Eigen::VectorXi>(size,low,high);
|
||
|
//
|
||
|
// Specifcally, this version will _always_ return an empty vector if size==0,
|
||
|
// regardless of the values for low and high. If size != 0, then this simply
|
||
|
// returns the result of Eigen::Derived::LinSpaced.
|
||
|
//
|
||
|
// Until this bug is fixed, we should also avoid calls to the member function
|
||
|
// `.setLinSpaced`. This means replacing:
|
||
|
//
|
||
|
// a.setLinSpaced(size,low,high);
|
||
|
//
|
||
|
// with
|
||
|
//
|
||
|
// a = igl::LinSpaced<decltype(a) >(size,low,high);
|
||
|
//
|
||
|
namespace igl
|
||
|
{
|
||
|
template <typename Derived>
|
||
|
//inline typename Eigen::DenseBase< Derived >::RandomAccessLinSpacedReturnType
|
||
|
inline Derived LinSpaced(
|
||
|
typename Derived::Index size,
|
||
|
const typename Derived::Scalar & low,
|
||
|
const typename Derived::Scalar & high);
|
||
|
}
|
||
|
|
||
|
// Implementation
|
||
|
|
||
|
template <typename Derived>
|
||
|
//inline typename Eigen::DenseBase< Derived >::RandomAccessLinSpacedReturnType
|
||
|
inline Derived
|
||
|
igl::LinSpaced(
|
||
|
typename Derived::Index size,
|
||
|
const typename Derived::Scalar & low,
|
||
|
const typename Derived::Scalar & high)
|
||
|
{
|
||
|
if(size == 0)
|
||
|
{
|
||
|
// Force empty vector with correct "RandomAccessLinSpacedReturnType" type.
|
||
|
return Derived::LinSpaced(0,0,1);
|
||
|
}else if(high < low)
|
||
|
{
|
||
|
return low-Derived::LinSpaced(size,low-low,low-high).array();
|
||
|
}else{
|
||
|
return Derived::LinSpaced(size,low,high);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
#endif
|