How can I make a vector in matlab, like vec(x)?

Hello all,

I am trying to replicate this formula:

I am doing so as follows:

Theta = A*B-C;
vTheta = vec(Theta');

A, B en C are defined. The problem is that Matlab does not seem to know the function 'vec' to do what I would like to do with Theta as in the formula...

How can I fix this?

Thanks in advance!

[John D'Errico]

Only you know what the vec function means. Non-standard notation means nothing to those who are not given the definition of that notation.

[Jan]

 The problem is that Matlab does not seem to know the function 'vec'

"Does not seem" or do you get a real error message? If Matlab does not have such a function, you can fix this by writing it.

Sorry for this trivial answer, but the provided details do not allow to give a more specific one.

[Marcos Caso-Huerta]

I think that Theta(:) is what you're looking for.

Answer 1

[Sean de Wolski]

I wrote a vec function in grad school for exactly this use. Here it is, authored almost exactly 7 years ago apparently!

attached.

Answer 2

[Giacomo Romanini]

Suppose you have a matrix X. You can obtain a vec(X) simply by the following:

   vecX = X(:);

[Jonathan]

Already answered in the comments (2 Jan 2018), so kudos to Marcos Caso-Huerta