"combos" <- function(n,p){ if(length(n) != 1){ n <- n[1] warning("Using first element as n") } if(length(p) != 1){ p <- p[1] warning("Using first element as p") } if(n != as.integer(n)){ warning("Coercing n to integer") n <- as.integer(n) } if(p != as.integer(p)){ warning("Coercing p to integer") p <- as.integer(p) } if(p > n) stop("p is greater than n") m <- choose(n,p) z <- .Fortran("combin", as.integer(n), as.integer(p), as.integer(m), a = integer(p*m), integer(n), integer(n), integer(n), PACKAGE = "quantreg") matrix(z$a,p) }