(no subject)

Dear Jacques Vernin (and All),

I appreciate that you are experiencing some difficulties when using R
and spatial extensions.

However, please realize that Roger Bivand has been wonderfully patient
and helpful to many, many people, as you can see in the history of
this email list.

Please remember that R and R spatial extensions are written,
maintained, and supported by volunteer labor.

Your email "tone of voice" is not very sweet, considering that you are
asking for free help.

regards,
-Frank Hardisty

~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Frank Hardisty
Department of Geography
University of South Carolina
hardisty at sc.edu
Office -- 803-777-5729
Fax -- 803-777-4972
http://people.cas.sc.edu/hardistf/


On 9/28/06, Frank Hardisty <HardistF at gwm.sc.edu> wrote:

---------- Forwarded message ----------
From: "pir2.jv" <pir2.jv at wanadoo.fr>
To: Roger.Bivand at nhh.no
Date: Thu, 28 Sep 2006 16:42:13 +0200
Subject: Re: [R-sig-Geo] (no subject)

Le 28 sept. 06 ? 16:18, Roger Bivand a ?crit :

If you say ls(), do the names of any of the objects begin with plot?

ls(pat="plot")

[1] "BBplot"             "Bplot"              "draw.plotmath.cell"
[4] "plot"               "plotG"              "plotM"
[7] "plotx"              "plotxx"

plotx, plotxx, plotG and plotM are functions of mine. Is there a
problem ?

The problem is that your local function plot is masking the one which
understands that "SpatialPolygons" objects have their own method
and need
to be sent there, so yes, at least your local plot is the problem. The
standard advice if you have a number of functions is to write a
package
with a NAMESPACE, and that will protect you from R not choosing the
one
you intended.

Why would be my function plot local ? It is not.
I removed the others

============

 > plot

function (x, y, ...)
{
     if (is.null(attr(x, "class")) && is.function(x)) {
         nms <- names(list(...))
         if (missing(y))
             y <- {
                 if (!"from" %in% nms)
                   0
                 else if (!"to" %in% nms)
                   1
                 else if (!"xlim" %in% nms)
                   NULL
             }
         if ("ylab" %in% nms)
             plot.function(x, y, ...)
         else plot.function(x, y, ylab = paste(deparse(substitute(x)),
             "(x)"), ...)
     }
     else UseMethod("plot")
}
<environment: namespace:graphics>

=============================

Jacques Vernin