Updating thin QR factorization
Updating the thin QR factorization of A when A is modified. These functions run faster than qr when the dimension of A is large, such as 5000-by-50.
Rank one update: rankoneupdate(Q, R, v, u):
Update the thin QR factorization of A when A = A + vu'.
Example:
A = rand(5,3);
v = rand(5,1);
u = rand(3,1);
[Q, R] = qr(A,0);
[Q_1, R_1] = rankoneupdate(Q, R, v, u);
Deleting a row: deleterow(Q, R, k)
Update the thin QR factorization of A when the kth row of A is deleted.
Example:
A = rand(5,3);
[Q, R] = qr(A, 0);
[Q_1, R_1] = deleterow(Q, R, 3);
Deleting a column: deletecolumn(Q, R, k)
Update the thin QR factorization of A when the kth column of A is deleted.
Example:
A = rand(5,3);
[Q, R] = qr(A, 0);
[Q_1, R_1] = deletecolumn(Q, R, 2);
Inserting a row: insertrow(Q, R, u, k)
Update the thin QR factorization of A when vector u is inserted as the kth row of A.
Example:
A = rand(5, 3);
[Q, R] = qr(A,0);
u = rand(3, 1);
[Q_1, R_1] = insertrow(Q, R, u, 2);
Inserting a row: insertcolumn(Q, R, u, k)
Update the thin QR factorization of A when vector u is inserted as the kth column of A.
Example:
A = rand(5, 3);
[Q, R] = qr(A,0);
u = rand(5, 1);
[Q_1, R_1] = insertcolumn(Q, R, u, 2);
Cite As
Meimei Chen (2025). Updating thin QR factorization (https://www.mathworks.com/matlabcentral/fileexchange/90835-updating-thin-qr-factorization), MATLAB Central File Exchange. Retrieved .
MATLAB Release Compatibility
Platform Compatibility
Windows macOS LinuxTags
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!Discover Live Editor
Create scripts with code, output, and formatted text in a single executable document.