spaninter - subspace intersection
computes the intersection of range( A ) and range( B ).
The first dim columns of X span this intersection i.e. X(:,1:dim) is an orthogonal basis for
range( A ) inter range( B )
In the X basis A and B are respectively represented by:
X'*A and X'*B .
tol is a threshold ( sqrt(%eps) is the default value).
A=rand(5,3)*rand(3,4); // A is 5 x 4, rank=3 B=[A(:,2),rand(5,1)]*rand(2,2); [X,dim]=spaninter(A,B); X1=X(:,1:dim); //The intersection svd(A),svd([X1,A]) // X1 in span(A) svd(B),svd([B,X1]) // X1 in span(B)
F. D.; ;