isKerAinKerB {distrMod} | R Documentation |
For two matrices A
and B
checks whether the null space of A
is a subspace
of the null space of B
, in other words, if Ax=0 entails Bx=0
.
isKerAinKerB(A, B, tol = .Machine$double.eps)
A |
a matrix; if A is a vector, A is coerced to a matrix by as.matrix . |
B |
a matrix; if B is a vector, B is coerced to a matrix by as.matrix . |
tol |
the tolerance for detecting linear dependencies in the
columns of a and up to which the two projectors are seen as equal (see below). |
via calls to svd
, the projectors pi_A and pi_B
onto the respective orthogonal complements of ker(A) and
ker(B) are calculated and then is checked whether
pi_B pi_A = pi_B.
logical
Peter Ruckdeschel Peter.Ruckdeschel@itwm.fraunhofer.de
ma <- cbind(1,1,c(1,1,7)) D <- t(ma %*% c(0,1,-1)) isKerAinKerB(D,ma) isKerAinKerB(ma,D)