Re: [eigen] Constructing a matrix by scalar*

Hell, I would love that to happen. Their math stuff is pretty unstructured and chaotic. But that's not something to be done during a masterthesis... I actually thought about it. But they have type independent arrays (And I don't like them...) with dynamic resizing etc...
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Thanks a lot for the advice. I guess the tutorial would have told me just as well - I just looked over the constructors...
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Gael Guennebaud wrote:
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I forgot to mention: a better option would be, of course, to port VTK to eigen2 ;)
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gael.

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On Thu, Nov 27, 2008 at 3:58 PM, Gael Guennebaud <gael.guennebaud@xxxxxxxxx <mailto:gael.guennebaud@xxxxxxxxx>> wrote:
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Hi,

typedef Map<Vector3f> Vector3fm;

then Vector3fm exactly represents what you were looking for. For
instance:

float d[3] = {1,2,3};
Vector3fm v(d);

v += Vector3::Random();

there is no copy, v stores only a single pointer. You can also
directly use a "Map" object:

Vector3f::Map(d) += Vector3::Random();

gael.

On Thu, Nov 27, 2008 at 3:45 PM, Benjamin Schindler
<bschindler@xxxxxxxxxxxxxxx <mailto:bschindler@xxxxxxxxxxxxxxx>>
wrote:

Hi

I'm currently working with vtk and it has a pretty ugly way of
dealing with vectors /- /at least in my opinion. So I thought
I could use eigen2 to do some of the fixed-size vector-math
I'm doing. I found that Matrix has a data() function which
returns a raw pointer to the data so that's good. But What I'm
missing is a constructor which constructs a i.e. vector3f from
a float pointer without copying the data. If I want to
efficiently interact between vtk and eigen, I think this is
very crucial.

Is this somehow possibel?

Thanks
Benjamin

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