1. ## QR Decomposition

I have a matrix consisting of two square matrices A & B

$
C = \begin {pmatrix} A \\ B \end{pmatrix}
$

and I want to perform QR decomposition on C, to obtain it's upper triangular factorization.

My question is, is it possible to perform QR decomposition on matrices A & B seperately, and somehow still obtain the upper triangular factorization of C?

2. Originally Posted by Superfish
I have a matrix consisting of two square matrices A & B

$
C = \begin {pmatrix} A \\ B \end{pmatrix}
$

and I want to perform QR decomposition on C, to obtain it's upper triangular factorization.

My question is, is it possible to perform QR decomposition on matrices A & B seperately, and somehow still obtain the upper triangular factorization of C?
I may not understand what you mean but R is always upper triangular.

3. Originally Posted by dwsmith
I may not understand what you mean but R is always upper triangular.
Sorry, i think you misunderstood.

I want to get the R matrix of C by performing QR decomposition on the square A and B matrices seperately.

4. So C is related to A and B via a binomial?

5. Originally Posted by dwsmith
So C is related to A and B via a binomial?
No, C is just matrix A stacked on top of matrix B. Wasn't sure what the latex command is for square brackets.