writing shapefiles using write.pointShape

I've been running gwr on some survey data and trying to write output 
back out to point shapefiles. At first, I thought that the shapefile 
wasn't being written, but after calling the file object I found it in a 
local settings/temp folder with a random shapefile name. I thought I had 
specified all that, but I'm obviously not familiar enough with the 
syntax to get it right. Would someone mind assisting me on this?  Code 
follows..
See ?tempfile, you were not using it correctly. Whether you should use it 
at all is of course also a good question - see below.

library(spgwr)
surveypts <- readShapePoints("C:/temp/NE_survey.shp", proj4string = 
CRS("+proj=aea +lat_0=96w +lat_1=29.5n +lat_2=45.5n"))
survey.bw <- gwr.sel(GHDENSITY ~ pca1 + PCA2 + PCA3 + PCA4 + PCA5, 
data=surveypts)
fitpts <- readShapePoints("C:/temp/fitpts.shp", proj4string = 
CRS("+proj=aea +lat_0=96w +lat_1=29.5n +lat_2=45.5n"))
OK so far.
fitpix <- SpatialPixels(fitpts, proj4string = CRS("+proj=aea +lat_0=96w 
+lat_1=29.5n +lat_2=45.5n"))
Why this step? It is unnecessary, just use fit.points=fitpts if the output 
Spatial*DataFrame is to be exported as a shapefile. If, on the other hand, 
you want to export it as a raster file, then don't try to write it as a 
shapefile.
surv.local <- ggwr(GHDENSITY ~ pca1 + PCA2 + PCA3 + PCA4 + PCA5, data = 
surveypts, bandwidth = survey.bw, gweight = gwr.Gauss, adapt = NULL, 
fit.points = fitpix, longlat = FALSE)
surv.local
Call:
ggwr(formula = GHDENSITY ~ pca1 + PCA2 + PCA3 + PCA4 + PCA5,
   data = surveypts, bandwidth = survey.bw, gweight = gwr.Gauss,
   adapt = NULL, fit.points = fitpix, longlat = FALSE)
Kernel function: gwr.Gauss
Fixed bandwidth: 22738.78
Summary of GWR coefficient estimates:
                  Min.    1st Qu.     Median    3rd Qu.       Max.   Global
X.Intercept. -4.176e+03 -9.067e+01 -3.565e+00  8.029e+01  4.402e+03 -73.5570
pca1         -2.567e+00 -2.289e-02 -1.725e-03  1.674e-02  3.135e-01  -0.0077
PCA2         -7.874e+01 -6.543e-01 -1.934e-01  2.298e-01  2.016e+01  -0.2667
PCA3         -8.844e+01 -1.236e+00 -1.109e-01  6.008e-01  1.469e+02   0.0202
PCA4         -1.272e+01 -3.509e-01  3.005e-01  1.178e+00  3.386e+02   0.8161
PCA5         -1.368e+02 -1.134e+00 -8.233e-03  9.222e-01  4.384e+01   0.6937

names(surv.local$SDF)
[1] "sum.w"           "X.Intercept."    "pca1"            "PCA2"            "PCA3"
[6] "PCA4"            "PCA5"            "dispersion"      "response_resids"

If fit.points=fitpts, surv.local$SDF would be a SpatialPointsDataFrame, so 
then just say

fn <- "whatever"
writePointsShape(surv.local$SDF, fn)

and you are done. If you only want pca1, then

writePointsShape(surv.local$SDF[, "pca1"], fn)

will write just that column. If you wanted a raster, fit.points=fitpix, 
and for example:

SGDF <- as(surv.local$SDF["pca1"], "SpatialGridDataFrame")
writeAsciiGrid(SGDF, fn)

will give you an Arc ASCII grid.
coords <- coordinates(fitpts)
pca1 <- cbind(coords, surv.local$SDF$pca1)
summary(pca1)
  coords.x1         coords.x2            V3
Min.   :-670120   Min.   :287533   Min.   :-2.566983
1st Qu.:-544120   1st Qu.:375533   1st Qu.:-0.022891
Median :-417620   Median :464533   Median :-0.001725
Mean   :-417620   Mean   :464533   Mean   :-0.047442
3rd Qu.:-291120   3rd Qu.:553533   3rd Qu.: 0.016741
Max.   :-165120   Max.   :641533   Max.   : 0.313544

class(pca1)
[1] "matrix"
dim(pca1)
[1] 179630      3
all(dim(dpca1 <- as.data.frame(pca1)) == c(179630,3))
[1] TRUE
summary(dpca1)
  coords.x1         coords.x2            V3
Min.   :-670120   Min.   :287533   Min.   :-2.566983
1st Qu.:-544120   1st Qu.:375533   1st Qu.:-0.022891
Median :-417620   Median :464533   Median :-0.001725
Mean   :-417620   Mean   :464533   Mean   :-0.047442
3rd Qu.:-291120   3rd Qu.:553533   3rd Qu.: 0.016741
Max.   :-165120   Max.   :641533   Max.   : 0.313544
class(dpca1)
[1] "data.frame"

B1pca1 <- tempfile("C:\temp")
write.pointShape(coords, df=dpca1, B1pca1, factor2char=TRUE)
(Where's the shapefile??)

B1pca1
[1] "C:\\DOCUME~1\\gcook\\LOCALS~1\\Temp\\Rtmpijon4d\\C:\temp1eb26e9"

You are getting exactly what you asked for - tempfile() is prepending 
"C:\temp" to the random suffix, and putting it into R's temporary 
directory as you requested.
After calling B1pca1, I find a randomly named shapefile (with .dbf and 
.shx)extensions in the .../Local Settings/Temp/ folder. I'm trying to 
name the file "B1pca1.shp" and I want it to go in the C:/Temp folder 
(for now). I've tried a few permutations of the last two commands, but 
I'm just not getting it right.
So say:

fn <- "C:/Temp/B1pca1"

and do not use tempfile(). For obvious reasons, the examples in the help 
pages use tempfile() to avoid messing up users' own work.

Roger
Thanks so much :)

Gericke

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Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Helleveien 30, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: Roger.Bivand at nhh.no

writing shapefiles using write.pointShape

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