R/getcmat.R

In SMARTAR: Sequential Multiple Assignment Randomized Trial and Adaptive Randomization

#getcmat() is the function to build the contrast design matrix

getcmat<-function(control,nats){
        CON<-control; G<-nats
        #total number of stragegies
        Cmat<-matrix(rep(0,G*(G-1)),ncol=G)
        #contrast matrix
        for (j in seq(G)){
             if (j==CON) {Cmat[ ,j]<- 1} else
             if (j<CON)  {Cmat[j,j]<--1} else
             if (j>CON)  {Cmat[j-1,j]<--1}
             }
        return(Cmat)
}