A function to output a correlation matrix with p-values and significance indicators in `R`.

corstars.R

corstars <- function(x){
    require(Hmisc)
    x <- as.matrix(x)
    R <- rcorr(x)$r
    p <- rcorr(x)$P
    mystars <- ifelse(p < .01, "**|", ifelse(p < .05, "* |", "  |"))
    R <- format(round(cbind(rep(-1.111, ncol(x)), R), 3))[,-1]
    Rnew <- matrix(paste(R, mystars, sep=""), ncol=ncol(x))
    diag(Rnew) <- paste(diag(R), "  |", sep="")
    rownames(Rnew) <- colnames(x)
    colnames(Rnew) <- paste(colnames(x), "|", sep="")
    Rnew <- as.data.frame(Rnew)
    return(Rnew)
    }