It seams that this function does not work when the argument cols is the character vector with the names of the columns. It seems to work only with column numbers
Try to run this example:
design=data.frame(A=as.factor(rep(1:4,2)),
B=as.factor(rep(1:2,rep(4,2))))
Y=cbind(Y1=rnorm(8),Y2=rnorm(8))
plotMeans(Y, design,cols ="Y1", x="A", z = "B")
It seams that this function does not work when the argument cols is the character vector with the names of the columns. It seems to work only with column numbers Try to run this example: design=data.frame(A=as.factor(rep(1:4,2)), B=as.factor(rep(1:2,rep(4,2)))) Y=cbind(Y1=rnorm(8),Y2=rnorm(8)) plotMeans(Y, design,cols ="Y1", x="A", z = "B")