On Mon, 20 Oct 2003, Laurent Gautier wrote: > I'd like to use optim, and give extra arguments to the objective > function. The man page says that the '...' should let one do it, > but I have a hard time to understand how.
Try reading up on argument matching, then. E.g. in `S Programming' (see the R FAQ). > Example: > > x <- 1:10 > y <- rnorm(10) > cost.f <- function(par, x, y) { > A <- par[1] > cost <- sum( (log(A*x) - log(y))^2) > return(cost) > } > > optim(3, cost.f, x, y) > ## returns: > Error in pmatch(x, table, duplicates.ok) : > argument is not of mode character > ## uh, uh... may the problem is with the argument matching ? > optim(3, cost.f, method="BFGS", x, y) > ## returns: > Error in log(A * x) : Argument "x" is missing, with no default > In addition: Warning message: > bounds can only be used with method L-BFGS-B in: optim(3, cost.f, method = "BFGS", > x, y) > > Any suggestion ? optim(3, cost.f, method="BFGS", x=x, y=y) except that some component of y is negative with high probability .... You do have to *name* arguments in ... -- that's standard S/R syntax. -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help