On Wed, 13 Oct 2010, jcress410 wrote: > u <- function(x) { > x1 <- x[1] > x2 <- x[2] > (x1^alpha)*(x2^(1-alpha)) > } > utility <- function(x) x[1]^(alpha)*x[2]^(1-alpha) > p <- c(2,1) > i <- -100 > alpha <- .3 > umax <- function(p,i,u) { > res <- constrOptim(c(.5,.5), u, grad=NULL, ui=-p, ci=i, mu = 1e-04, > control=list(fnscale=-1)) > return(res) > } > curve(umax, c(c(2,1),c(2,1)), c(10,100))
I don't see any question here. However you must RTFM. 1) The returned value of umax() is a list. How do you expect curve() to plot a list? 2) curve() requires that the function umax() must be vectorisable wrt its first parameter, i.e. you pass it a numeric vector and it returns a numeric vector of the same length. 3) you have to realise that curve() will only graph a 1-dimensional function HTH, Ray ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.