Half-vectorisation function in MATLAB

Is there a specific matlab function for a half vectorisation that from square matrix to row vector? I know we can use the reshape function for full vectorization from a 2x2 square matrix to column vector of 4x1.

Example of Half-vectorisation:

[x1x1,x1x2;x2x1,x2x1] to a [x1x1;2*x1x2; x2x2] so from 2x2 square matrix to row vector of 3x1

or

[x1x1,x1x2,x1x3;x2x1,x2x2,x2x3;x3x1,x3x2,x3x3] to a [x1x1;2*x1x2;2*x1x3;x2x2;2*x2x3;x3x3] from 3x3 square matrix to a row vector of 6x1

so its similar to taking the upper triangular of the square matrix

[Stephen23]

https://en.wikipedia.org/wiki/Duplication_and_elimination_matrices

https://www.mathworks.com/matlabcentral/fileexchange/23391-triangular-and-diagonal-indexing

https://www.mathworks.com/matlabcentral/answers/274256-algorithm-for-an-elimination-matrix