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Shijun
Posts:
1
Registered:
12/12/12


Re: How to reduce a sigular matrix to a full rank matrix in matlab
Posted:
Dec 12, 2012 3:32 AM


use function rref, if A is a n by m matrix, and n>=m, [~, jb]= rref(A); Then the full rank matrix is A_f= A(:, jb);
zbxu@ucolick.org (oasis) wrote in message <b6b43b21.0402092021.c3a147b@posting.google.com>... > the rank of the new matrix is not full > "Giampy" <campa@cemr.wvu.edu> wrote in message news:<bvujou$1111h3$1@ID97186.news.uniberlin.de>... > > > Actually it doesn't work,the rank for the new matrix is 64, it seems > > > > > > if you use as second row > > > > k=rank(A80); > > idx=1:k; > > > > it gives a k*k matrices > > > > you mean that the rank of the resulting matrix is not full ?? > > > > > > > strange because from the theory, it should work. > > > "Giampy" <campa@cemr.wvu.edu> wrote in message > > news:<bvtkrp$104n6d$1@ID97186.news.uniberlin.de>... > > > > > How to find the linear dependent column/row > > > > > > > > i am not sure why you want to do that, > > > > one way would be : > > > > > > > > [U,S,V]=svd(A80); > > > > idx=find(diag(S)>1e15); > > > > A72=U(idx,idx)*S(idx,idx)*V(idx,idx)'; > > > > > > > > but i think you should have a careful look to orth, null > > > > and related functions before you do anything, > > > > since there is probably a more straightforward way > > > > to do whatever you are trying to do ... > > > > > > > > giampy



