I am having difficulty loading a points shapefile (1600 records) I generated
from ArcGIS as a PointsSpatialDataFrame using the maptools readShapePoints
function.
library(maptools)
surveypts <- readShapePoints(system.file("C:/temp/survey.shp",
package="maptools")[1]
Error in getinfo.shape(filen) : Error opening SHP file
I've tried numerous re-exports and renames of the dataset, to no avail.
I've also tried placing the shapefile in the library's shapefile folder,
with the example dataset (see example below).
x <- readShapePoints(system.file("shapes/survey.shp",
package="maptools")[1]
No luck there either. I'm quite new to R, but I can follow a manual and
google well enough. However, I haven't seen anything to help me. The example
point datasets load fine. I figure that I'm missing on some familiarity with
R and that I don't know the tricks yet. Any help?
Thanks in advance.
Gericke Cook
USDA-APHIS-PPQ
gerickes at earthlink.net schreef:> I am having difficulty loading a points shapefile (1600 records) I generated from ArcGIS as a PointsSpatialDataFrame using the maptools readShapePoints function. > > library(maptools) > surveypts <- readShapePoints(system.file("C:/temp/survey.shp", package="maptools")[1] > Error in getinfo.shape(filen) : Error opening SHP file > > I've tried numerous re-exports and renames of the dataset, to no avail. I've also tried placing the shapefile in the library's shapefile folder, with the example dataset (see example below). > > x <- readShapePoints(system.file("shapes/survey.shp", package="maptools")[1] > > No luck there either. I'm quite new to R, but I can follow a manual and google well enough. However, I haven't seen anything to help me. The example point datasets load fine. I figure that I'm missing on some familiarity with R and that I don't know the tricks yet. Any help? > > Thanks in advance. > > Gericke Cook > USDA-APHIS-PPQ > > ______________________________________________ > 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. >Hi Gericke, Why do you use system.file? Probably it will look for survey.shp in the maptools package. Try instead: surveypts <- readShapePoints("C:/temp/survey.shp") For these kind of geographic questions, the r-sig-geo mailing list is maybe a better way to get good answers. cheers and hth, Paul -- Drs. Paul Hiemstra Department of Physical Geography Faculty of Geosciences University of Utrecht Heidelberglaan 2 P.O. Box 80.115 3508 TC Utrecht Phone: +31302535773 Fax: +31302531145 http://intamap.geo.uu.nl/~paul
The help page for readShapePoints says that the file name that you
supply should not include the extension.
The "system.file" part of the example in the help page is only to use
the example file that came with the package. Since you want to open
your own file you omit the system.file() bit.
Do something like:
readShapePoints( 'C:/path_to_my_file/filename')
Hope this helps.
-Don
At 12:05 PM -0600 3/11/08, gerickes at earthlink.net
wrote:>I am having difficulty loading a points shapefile (1600 records) I
>generated from ArcGIS as a PointsSpatialDataFrame using the maptools
>readShapePoints function.
>
>library(maptools)
>surveypts <- readShapePoints(system.file("C:/temp/survey.shp",
>package="maptools")[1]
>Error in getinfo.shape(filen) : Error opening SHP file
>
>I've tried numerous re-exports and renames of the dataset, to no
>avail. I've also tried placing the shapefile in the library's
>shapefile folder, with the example dataset (see example below).
>
>x <- readShapePoints(system.file("shapes/survey.shp",
package="maptools")[1]
>
>No luck there either. I'm quite new to R, but I can follow a manual
>and google well enough. However, I haven't seen anything to help me.
>The example point datasets load fine. I figure that I'm missing on
>some familiarity with R and that I don't know the tricks yet. Any
>help?
>
>Thanks in advance.
>
>Gericke Cook
>USDA-APHIS-PPQ
>
>______________________________________________
>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.
--
---------------------------------
Don MacQueen
Lawrence Livermore National Laboratory
Livermore, CA, USA
925-423-1062
macq at llnl.gov