R/mat2list_1.R

In musto101/wilcox_R: What the package does (short line)

MAT2list <-
function(x,J=NULL,p=NULL){
#
# Store the data in a matrix or data frame in a new
# R variable having list mode.
# The results are stored in y, having list mode
# Col 1 to p of x will be stored as a matrix in  y[[1]],
# Col p+1 to 2p are stored  in y[[2]], and so on.
#
# The function assumes ncol(x)=J*P
# either J, the number of groups, or p, the number of variables,
# must be specified.
#
#  This function is used by the R function linconMpb when testing
#  hypotheses about linear contrasts based on multvariate data.
#
if(is.null(dim(x)))stop("The argument x must be a matrix or data frame")
y<-list()
if(is.null(J) && is.null(p))stop("Specify J or P")
if(is.null(J))J=ncol(x)/p
if(is.null(p))p=ncol(x)/J
Jp=floor(J)*floor(p)
if(Jp != ncol(x))stop("Jp is not equal to the number of columns")
lp=1-p
up=0
for(j in 1:J){
lp=lp+p
up=up+p
y[[j]]<-as.matrix(x[,lp:up])
}
y
}