doBy (version 4.4.0)

utils: Utility functions

Description

Utility functions not te be used directly by the user.

Usage

makeSparse(X)
ij2r(i,j,N)
indexSymmat2vec(i,j,N)
indexVec2Symmat(k,N)

Arguments

X

A matrix to be turned into a sparse matrix.

N

number of columns of a matrix

i

row index of a matrix

j

column index of a matrix

k

vector index

Details

makeSparse turns a matrix into a sparse matrix using sparseMatrix of the Matrix package. ij2r, indexSymmat2vec and indexVec2Symmat are index functions. Let Q[i,j] be a quadratic matrix of dimesnion N and q=Q[1,1],Q[1,2],...,Q[1,N],Q[2,1],..Q[N,N] the row major vectorization of the matrix. Then Q[i,j]<-q[ij2r(r)]. Let S[i,j] be a symmetric matrix of dimension N and s=S[1,1],S[1,2],...,S[1,N],S[2,3],..,S[N-1,N],S[N,N] the row major vecotorization of the upper triangular part of S. Then s[indexSymmat2vec(i,j,N)]<-S[i,j] and S[indexVec2Symmat(r,N)]<-s[r].

See Also

KRmodcomp,lmer.