#rpca command
rpca <- function(dat)
{
    dat <- dat[complete.cases(dat),]
    nr <- nrow(dat)
    nc <- ncol(dat)
    heikin <- apply(dat, 2, mean)
    bunsan <- apply(dat, 2, var)
    sd <- sqrt(bunsan)
    eval <- (result <- eigen(r <-cor(dat)))$values
    evec <- result$vectors
    cum.contr <- cumsum(contr <- eval/nc*100)
    fl <- sqrt(matrix(eval, nc, nc, byrow=TRUE))*evec
    fs <- scale(dat)%*%evec*sqrt(nr/(nr-1))

    names(heikin) <- names(bunsan) <- names(sd) <- rownames(r) <- colnames(r) <- rownames(fl) <- paste("Var",1:nc)
    names(eval) <- names(contr) <- names(cum.contr) <- colnames(fl) <- colnames(fs) <- paste("PC", 1:nc)
    list(mean=heikin, variance=bunsan, standard.deviation=sd, r=r, factor.loadings=fl, eval=eval, contribution=contr, cum.contribution=cum.contr, fs=fs)
}