Syntax: @vech(o)

Argument: matrix, sym, o

Return: vector

Creates a vector from the columns of the lower triangle of the source square matrix o stacked on top of each another. The vector has the same number of elements as the source matrix has in its lower triangle. Example:

sym s1 = @mrnd(5,5)

vector v1 = @vech(m1)

creates a sym matrix S1 and stacks its lower triangle in a 15 element vector V1.

See also @unvech.