vec
Vectorisation of a matrix.
Syntax

vec(A)

A
is a matrix

Description
If A
is a matrix, then vec(A)
is the vectorisation of A
, that is, the vector obtained by concatenating the columns of A
, from left to right.
Notes
vectorization
and vec
are synonyms.
To obtain the vector obtained by concatenating the rows of A
, from top to bottom, simply “cast” the matrix to a vector using the vector
function.
Examples
A ≔ ❨❨2, 1, −i❩, ❨1, 0, 2❩, ❨4, i, 2❩, ❨0, 1, −1❩❩
⎛ 2 1 −i⎞ ⎜ 1 0 2⎟ ⎜ 4 i 2⎟ ⎝ 0 1 −1⎠
vec(A)
(2, 1, 4, 0, 1, 0, i, 1, −i, 2, 2, −1)