Re: [eigen] Std Vector again

[Keir Mierle <mierle@xxxxxxxxx>]

We don't use boost, and plan to keep it that way. It's an enormous dependency. It's tangled enough that they have a special utility to extract subsets of boost. I tried it, and the 'subsets' are still large, even when extracting a single header (e.g. tuple or scoped_ptr).

Keir

On Fri, Jun 26, 2009 at 12:25 PM, Patrick Mihelich <patrick.mihelich@xxxxxxxxx> wrote:

Keir,

If you are already using Boost, I suggest sidestepping the Eigen/std::vector quandary and instead using the vector implementation in Boost.Interprocess for Eigen types. Although it (currently) lives in Interprocess, it's a fully generic implementation of STL vector that fixes the resize flaw and has some other niceties such as support for move semantics.

Current C++ may not have templated typedefs, but you can get some of the same benefits from a simple meta-program:

#include <boost/interprocess/containers/vector..hpp>

template<typename T>
struct AlignedVector
{
  typedef boost::interprocess::vector<T, Eigen::aligned_allocator<T> > type;
};

AlignedVector<Vector4f>::type my_vec;

Cheers,
Patrick

On Fri, Jun 26, 2009 at 10:37 AM, Benoit Jacob <jacob.benoit.1@xxxxxxxxx> wrote:

2009/6/26 Benoit Jacob <jacob.benoit.1@xxxxxxxxx>:

> What you want here is EIGEN_DONT_ALIGN but this option is only
> available in the development version.
>
> In Eigen 2.0.3, to disable alignment, you'll have to edit
> Eigen/src/Core/util/Macros.h and at line 44 replace
>
> #if !defined(__GNUC__) || defined(__i386__) || defined(__x86_64__) ||
> defined(__ppc__) || defined(__ia64__)
>
> by
>
> #if 0

And by the way, you can control that on a per-matrix basis by using e..g.

Eigen::Matrix<float,4,1,Eigen::DontAlign>

instead of

Eigen::Vector4f

Cheers,
Benoit