Re: [eigen] [FAQ] how to have an initialized static Matrix

[Christoph Hertzberg <chtz@xxxxxxxxxxxxxxxxxxxxxxxx>]

On 21.03.2013 11:36, Christoph Hertzberg wrote:
> On 21.03.2013 10:30, Helmut Jarausch wrote:
> > unfortunately, Eigen's elegant initialization is an expression.
> >
> > Is there an "elegant" solution for this ugly code (within a function)
> >
> >
> >    static double _C[6] = { 1.0 / 5, 3.0 / 10, 4.0 / 5, 8.0 / 9, 1.0,
> > 1.0 };
> >    static const Eigen::Map<Eigen::Matrix<double,6,1>,0> C((double*)_C);

I found another very hacked solution. It requires that the data layout 
of Matrix will not change (especially, no extra fields will be introduced):

EIGEN_ALIGN16
static const double C3_data[] = {1.0/5, 3.0/10, 4.0/5, 8.0/9, 1.0, 1.0};
static const Vec6d& C3 = reinterpret_cast<const Vec6d&>(*C3_data);


Christoph





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Dipl.-Inf., Dipl.-Math. Christoph Hertzberg
Cartesium 0.049
Universität Bremen
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