R help - Oct 2008 - Source code for ppr (Projection Pursuit Regression)

Dear R users,

I am looking for the source code of the implementation of ppr (Projection
Pursuit Regression) in R.

It will be great if citations of the source papers on which the
implementation is based, are also provided.

Thank you,
Arvind Iyer,
Grad student, Deptt. of Biomedical Engineering
Viterbi School of Engineering
University of Southern California, Los Angeles

	[[alternative HTML version deleted]]

To get the references, check ?ppr

For the code:
> methods(ppr)
[1] ppr.default* ppr.formula*

   Non-visible functions are asterisked
> getAnywhere(ppr.default)
A single object matching 'ppr.default' was found
It was found in the following places
  registered S3 method for ppr from namespace stats
  namespace:stats
with value

function (x, y, weights = rep(1, n), ww = rep(1, q), nterms,
    max.terms = nterms, optlevel = 2, sm.method = c("supsmu",
        "spline", "gcvspline"), bass = 0, span = 0, df = 5,
gcvpen = 1,
    ...)
{
    call <- match.call()
    call[[1]] <- as.name("ppr")
    sm.method <- match.arg(sm.method)
    ism <- switch(sm.method, supsmu = 0, spline = 1, gcvspline = 2)
    if (missing(nterms))
        stop("'nterms' is missing with no default")
    mu <- nterms
    ml <- max.terms
    x <- as.matrix(x)
    y <- as.matrix(y)
    if (!is.numeric(x) || !is.numeric(y))
        stop("'ppr' applies only to numerical variables")
    n <- nrow(x)
    if (nrow(y) != n)
        stop("mismatched 'x' and 'y'")
    p <- ncol(x)
    q <- ncol(y)
    if (!is.null(dimnames(x)))
        xnames <- dimnames(x)[[2]]
    else xnames <- paste("X", 1:p, sep = "")
    if (!is.null(dimnames(y)))
        ynames <- dimnames(y)[[2]]
    else ynames <- paste("Y", 1:q, sep = "")
    msmod <- ml * (p + q + 2 * n) + q + 7 + ml + 1
    nsp <- n * (q + 15) + q + 3 * p
    ndp <- p * (p + 1)/2 + 6 * p
    .Fortran(R_setppr, as.double(span), as.double(bass), as.integer(optlevel),
        as.integer(ism), as.double(df), as.double(gcvpen))
    Z <- .Fortran(R_smart, as.integer(ml), as.integer(mu), as.integer(p),
        as.integer(q), as.integer(n), as.double(weights), as.double(t(x)),
        as.double(t(y)), as.double(ww), smod = double(msmod),
        as.integer(msmod), double(nsp), as.integer(nsp), double(ndp),
        as.integer(ndp), edf = double(ml))
    smod <- Z$smod
    ys <- smod[q + 6]
    tnames <- paste("term", 1:mu)
    alpha <- matrix(smod[q + 6 + 1:(p * mu)], p, mu, dimnames = list(xnames,
        tnames))
    beta <- matrix(smod[q + 6 + p * ml + 1:(q * mu)], q, mu,
        dimnames = list(ynames, tnames))
    fitted <- drop(matrix(.Fortran(R_pppred, as.integer(nrow(x)),
        as.double(x), as.double(smod), y = double(nrow(x) * q),
        double(2 * smod[4]))$y, ncol = q, dimnames = dimnames(y)))
    jt <- q + 7 + ml * (p + q + 2 * n)
    gof <- smod[jt] * n * ys^2
    gofn <- smod[jt + 1:ml] * n * ys^2
    jf <- q + 6 + ml * (p + q)
    smod <- smod[c(1:(q + 6 + p * mu), q + 6 + p * ml + 1:(q *
        mu), jf + 1:(mu * n), jf + ml * n + 1:(mu * n))]
    smod[1] <- mu
    structure(list(call = call, mu = mu, ml = ml, p = p, q = q,
        gof = gof, gofn = gofn, df = df, edf = Z$edf[1:mu], xnames = xnames,
        ynames = ynames, alpha = drop(alpha), beta = ys * drop(beta),
        yb = smod[5 + 1:q], ys = ys, fitted.values = fitted,
        residuals = drop(y - fitted), smod = smod), class = "ppr")
}
<environment: namespace:stats>
>
Hope this helps!

Sincerely,
Erin


On Tue, Oct 28, 2008 at 10:53 AM, Arvind Iyer <arvind.v.iyer at gmail.com>
wrote:
> Dear R users,
>
> I am looking for the source code of the implementation of ppr (Projection
> Pursuit Regression) in R.
>
> It will be great if citations of the source papers on which the
> implementation is based, are also provided.
>
> Thank you,
> Arvind Iyer,
> Grad student, Deptt. of Biomedical Engineering
> Viterbi School of Engineering
> University of Southern California, Los Angeles
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.
>


-- 
Erin Hodgess
Associate Professor
Department of Computer and Mathematical Sciences
University of Houston - Downtown
mailto: erinm.hodgess at gmail.com