c++ - Armadillo - fill a matrix from the values in a column vector -

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i go , forth between arma::mat of size m x n , arma::vec of size mn (which column-major linearization of matrix).

i can go matrix vector using arma::vectorise, i.e.

arma::vec vector = arma::vectorise(matrix);

however, cannot find simple way go other way around. insert first m values of vector in first column of matrix, second m values in second column , on. there way efficiently?

make memory matrix shared vector using advanced constructors:

mat x(4,5);  vec v(x.memptr(), x.n_elem, false, false);  // changing elements in x or v affect both

as long operations don't cause aliasing or change size of either x or v, 2 objects keep sharing memory.


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