| fixDependence {mgcv} | R Documentation |
Identifies columns of a matrix X2 which are linearly
dependent on columns of a matrix X1. Primarily of use in setting up
identifiability constraints for nested GAMs.
fixDependence(X1,X2,tol=.Machine$double.eps^.5)
X1 |
A matrix. |
X2 |
A matrix, the columns of which may be partially linearly
dependent on the columns of X1. |
tol |
The tolerance to use when assessing linear dependence. |
The algorithm uses a simple approach based on QR decomposition: see Wood (2006, section 4.10.2) for details.
An array of the columns of X2 which are linearly dependent on
columns of X1. NULL if the two matrices are independent.
Simon N. Wood simon.wood@r-project.org
Wood S.N. (2006) Generalized Additive Models: An Introduction with R. Chapman and Hall/CRC Press.
n<-20;c1<-4;c2<-7 X1<-matrix(runif(n*c1),n,c1) X2<-matrix(runif(n*c2),n,c2) X2[,3]<-X1[,2]+X2[,4]*.1 X2[,5]<-X1[,1]*.2+X1[,2]*.04 fixDependence(X1,X2)