Re: [eigen] fix double-promotion in 3.3 Core/SpecialFunctions.h

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On 2016-05-05 15:04, Ilja Honkonen wrote:
Looks like boost has this covered:
This overload would be nice for Eigen types also.

I'm really not sure how often this is needed and I guess this is very hard to implement optimally, e.g. for big matrices it could be worth to implementing pow<31>(A) as
in case A is invertible.

And it gets really complicated if powers are part of bigger expressions, like for matrix A and vector x
might be cheapest to compute by k Matrix-vector products (which is O(k*n²) before doing any O(n³) matrix products.

Also, for Arrays the exponentiation should happen packet-by-packet if possible, of course.

But if someone likes to implement that, I would not object integrating it into Eigen.


 Dipl. Inf., Dipl. Math. Christoph Hertzberg

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