diff options
author | Gael Guennebaud <g.gael@free.fr> | 2018-07-23 16:20:25 +0200 |
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committer | Gael Guennebaud <g.gael@free.fr> | 2018-07-23 16:20:25 +0200 |
commit | c747cde69a9ab286984a09223c3f477b782a6617 (patch) | |
tree | 570a6a08bd400a4511a1e1d63de32fb1663b72d7 /Eigen/src/Core/ArithmeticSequence.h | |
parent | 2bf864f1eb1b2497d28747c7f77ec3e2f1e8d9d2 (diff) |
Add lastN shorcuts to seq/seqN.
Diffstat (limited to 'Eigen/src/Core/ArithmeticSequence.h')
-rw-r--r-- | Eigen/src/Core/ArithmeticSequence.h | 34 |
1 files changed, 32 insertions, 2 deletions
diff --git a/Eigen/src/Core/ArithmeticSequence.h b/Eigen/src/Core/ArithmeticSequence.h index ada1571f1..2083cf178 100644 --- a/Eigen/src/Core/ArithmeticSequence.h +++ b/Eigen/src/Core/ArithmeticSequence.h @@ -225,7 +225,8 @@ auto seq(FirstType f, LastType l, IncrType incr) -typename internal::cleanup_index_type<FirstType>::type(f)+CleanedIncrType(incr)) / CleanedIncrType(incr), CleanedIncrType(incr)); } -#else + +#else // EIGEN_HAS_CXX11 template<typename FirstType,typename LastType> typename internal::enable_if<!(Symbolic::is_symbolic<FirstType>::value || Symbolic::is_symbolic<LastType>::value), @@ -314,10 +315,39 @@ seq(const Symbolic::BaseExpr<FirstTypeDerived> &f, const Symbolic::BaseExpr<Last typedef typename internal::cleanup_seq_incr<IncrType>::type CleanedIncrType; return seqN(f.derived(),(l.derived()-f.derived()+CleanedIncrType(incr))/CleanedIncrType(incr), incr); } -#endif +#endif // EIGEN_HAS_CXX11 #endif // EIGEN_PARSED_BY_DOXYGEN + +#if EIGEN_HAS_CXX11 +/** \cpp11 + * \returns a symbolic ArithmeticSequence representing the last \a size elements with increment \a incr. + * + * It is a shortcut for: \code seqN(last-(size-fix<1>)*incr, size, incr) \endcode + * + * \sa lastN(SizeType), seqN(FirstType,SizeType), seq(FirstType,LastType,IncrType) */ +template<typename SizeType,typename IncrType> +auto lastN(SizeType size, IncrType incr) +-> decltype(seqN(Eigen::placeholders::last-(size-fix<1>())*incr, size, incr)) +{ + return seqN(Eigen::placeholders::last-(size-fix<1>())*incr, size, incr); +} + +/** \cpp11 + * \returns a symbolic ArithmeticSequence representing the last \a size elements with a unit increment. + * + * It is a shortcut for: \code seq(last+fix<1>-size, last) \endcode + * + * \sa lastN(SizeType,IncrType, seqN(FirstType,SizeType), seq(FirstType,LastType) */ +template<typename SizeType> +auto lastN(SizeType size) +-> decltype(seqN(Eigen::placeholders::last+fix<1>()-size, size)) +{ + return seqN(Eigen::placeholders::last+fix<1>()-size, size); +} +#endif + namespace internal { // Convert a symbolic span into a usable one (i.e., remove last/end "keywords") |