Re: [eigen] Coercion of matrices with mixed types ?

[Christoph Hertzberg <chtz@xxxxxxxxxxxxxxxxxxxxxxxx>]

On 04.08.2012 16:52, Brad Bell wrote:
> It appears that Eigen will not coerce matrices, even if the scalar type
> does. Is this a design decision or am I missing something ?

It's a design decision.

> [...]
>
> int main(void)
> {    typedef Eigen::Matrix<     double, Eigen::Dynamic, 1  > d_vector;
>       typedef Eigen::Matrix< OTHER_TYPE, Eigen::Dynamic, 1  > other_vector;
>
>       size_t n = 10;
>       other_vector  u(n);
>       d_vector  v(n), w(n);
> [...]
>       w = v - u;

You need to cast u to double here:
	w = v - u.cast<double>();

Be aware that in some cases you need to write
	u.template cast<double>(),
not in this case, though. See here:
http://eigen.tuxfamily.org/dox-devel/TopicTemplateKeyword.html



Christoph



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Dipl.-Inf. Christoph Hertzberg
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