isKerAinKerB {distrMod} | R Documentation |
isKerAinKerB
Description
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
.
Usage
isKerAinKerB(A, B, tol = .Machine$double.eps)
Arguments
A |
a matrix; if |
B |
a matrix; if |
tol |
the tolerance for detecting linear dependencies in the
columns of |
Details
via calls to svd
, the projectors \pi_A
and \pi_B
onto the respective orthogonal complements of {\rm ker}(A)
and
{\rm ker}(B)
are calculated and then is checked whether
\pi_B\pi_A=\pi_B
.
Value
logical
Author(s)
Peter Ruckdeschel peter.ruckdeschel@uni-oldenburg.de
Examples
ma <- cbind(1,1,c(1,1,7))
D <- t(ma %*% c(0,1,-1))
## IGNORE_RDIFF_BEGIN
## note that results may vary according to BLAS
isKerAinKerB(D,ma)
isKerAinKerB(ma,D)
## IGNORE_RDIFF_END
[Package distrMod version 2.9.1 Index]