Matrix division operator in RATS

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jonasdovern
Posts: 97
Joined: Sat Apr 11, 2009 10:30 am

Matrix division operator in RATS

Unread post by jonasdovern »

Is there a command in RATS that is equivalent to the matrix division command "\" in Matlab (e.g. A\B) for the case that A is an M-by-N matrix with N > or < M? (I reckon that for an N-by-N matrix A, %solve(A,B) will do the trick.)

From the Matlab expanation:
If A is an M-by-N matrix with M < or > N and B is a column vector with M components, or a matrix with several such columns, then X = A\B is the solution in the least squares sense to the under- or overdetermined system of equations A*X = B. The effective rank, K, of A is determined from the QR decomposition with pivoting. A solution X is computed which has at most K nonzero components per column. If K < N this will usually not be the same solution as PINV(A)*B. A\EYE(SIZE(A)) produces a generalized inverse of A.
Thanks a lot for any hint.
TomDoan
Posts: 7814
Joined: Wed Nov 01, 2006 4:36 pm

Re: Matrix division operator in RATS

Unread post by TomDoan »

It sounds like that would just be %GINV(A)*B
jonasdovern
Posts: 97
Joined: Sat Apr 11, 2009 10:30 am

Re: Matrix division operator in RATS

Unread post by jonasdovern »

Thanks. This is working. Results are numerically identical to those obtained in Matlab.
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