.Internal
G'day Kevin, On Wed, 18 Mar 2009 21:46:51 -0700
<rkevinburton at charter.net> wrote:
I was trying to find source for optimize and I ran across
function (f, interval, ..., lower = min(interval), upper =
max(interval), maximum = FALSE, tol = .Machine$double.eps^0.25)
{
if (maximum) {
val <- .Internal(fmin(function(arg) -f(arg, ...), lower,
upper, tol))
list(maximum = val, objective = f(val, ...))
}
else {
val <- .Internal(fmin(function(arg) f(arg, ...), lower,
upper, tol))
list(minimum = val, objective = f(val, ...))
}
}
Then I did a search for fmin and i came up with:
/* fmin(f, xmin, xmax tol) */
SEXP attribute_hidden do_fmin(SEXP call, SEXP op, SEXP args, SEXP rho)
So my question is where do I find the intermediary step between
.Internal(fmin(function(arg) f(arg, ...), lower, upper, tol))
and
SEXP attribute_hidden do_fmin(SEXP call, SEXP op, SEXP args, SEXP rho)
@Article{Rnews:Ligges:2006,
author = {Uwe Ligges},
title = {{R} {H}elp {D}esk: {Accessing} the Sources},
journal = {R News},
year = 2006,
volume = 6,
number = 4,
pages = {43--45},
month = {October},
url = http,
pdf = Rnews2006-4
}
http://CRAN.R-project.org/doc/Rnews/Rnews_2006-4.pdf
The number of arguments doesn't match up. I am guessing that lower and upper somehow get merged into the args. And rho is 'tol'. Right?
Unlikely. In "Writing R Extensions" (and the functions I looked up), 'rho' usually denotes an environment that is used to evaluate expressions in. Typically (i.e. in cases that I had need to look at), all arguments are rolled into the SEXP arg for internal functions. HTH. Cheers, Berwin