Rank deficient overdeterminated linear system

Hi

I have an overdeterminated system and my coefficient matrix is not full rank.

I try solving it with SVD or QR but because of rank deficiency I obtain wrong answer. Somone can axplain for me how I can achieve correct answer for this system?

Answer 1

[Matt J]

If the matrix is rank deficient, it cannot be over-determined. Try PINV, but realize that the solution space is not unique.

[mohsen]

I use Pinv already . I wanna an unique answer .

[Matt J]

Again, your equations can't have a unique solution if indeed they are rank defficient. You need more equations.