Hi,

I would like to know whether it is possible to initialize an Eigen Vector/Array from a continuous memory block without copying data. Something like:

Code: Select all

 
double * data = new double[10];
VectorXd vec(data, 10);


I have not found anything in the documentation about this.


Thank you for any answer,

Tobi

I believe you want:

Code: Select all

double * data = new double[10];
Eigen::Map<Eigen::VectorXd> vec(data, 10);

Thanks for the answer. This seems to be what I am looking for. But can I compute with the map as it would be a VectorXd? Or are there restrictions. For instance can I add a VectorXd and a Map yielding a VectorXd?

Tobi

I'm fairly new to Eigen, but I believe that is the purpose of Maps.

Manhigh is right. The only practical difference is that you cannot resize a Map object since it does not hold the underlying memory.

Thanks a lot for your answers. This is exactly what I was looking for. By the way, I am quite impressed by Eigen. Great work