[R] Error opening SHP file

[David Winsemius]

> On Jan 22, 2016, at 9:24 AM, Amoy Yang via R-help <r-help at r-project.org> wrote:
> 
> This is the results that addresses David's advice.
>> library(maptools)
>> library(maps)
>> state.map <- readShapeSpatial("maps/st24_d00.shp")
> Error in getinfo.shape(fn) : Error opening SHP file
>> # David question: What does list.files('maps') return? Is there a 'st24_d00.shp' value in there?
>> list.files('maps')
> character(0)
> I actually use the link below to learn how to load state/zip-data on USA map.

That link says:

"For example (assumes you have the maryland shapefiles in the map subdirectory):"

So it did not purport to tell you how to put shape files in that subdirectory. That statement assumed you understood basic OS path naming conventions in your unstated OS and how to move files around, which is not a topic for rhelp.

Try working through the examples in the documents that come with the `sp`-package.

-- 
David.
> 
> # http://stackoverflow.com/questions/1441717/plotting-color-map-with-zip-codes-in-r-or-python
> Plotting color map with zip codes in R or Python
> |   |
> |   |  |   |   |   |   |   |
> | Plotting color map with zip codes in R or PythonI have some US demographic and firmographic data. I would like to plot zipcode areas in a state or a smaller region (e.g. city). Each area would be annotated by col... |
> |  |
> | View on stackoverflow.com | Preview by Yahoo |
> |  |
> |   |
> 
>    On Friday, January 22, 2016 10:03 AM, Barry Rowlingson <b.rowlingson at lancaster.ac.uk> wrote:
> 
> 
> We can duplicate the error by giving a path to a non-existent
> shapefile, which is probably the original problem:
> 
>> require(maptools)
> Loading required package: maptools
> Loading required package: sp
> Checking rgeos availability: TRUE
>> foo=readShapeSpatial("fnord.shp")
> Error in getinfo.shape(fn) : Error opening SHP file
> 
> The error message there isn't totally explicit, and might cover a
> range of other possibilities such as a corrupted shapefile, or a
> missing .shx component of the shapefile or whatever.
> 
> BUT you probably shouldn't be using readShapeSpatial anyway, as it has
> a habit of not reading the coordinate system in the .prj file. I find
> it much easier to use `raster::shapefile` which *does* read the
> coordinate system *and* gives a more explicit error message for a
> missing shapefile:
> 
>> require(raster)
> Loading required package: raster
>> foo=shapefile("fnord.shp")
> Error in normalizePath(x, winslash = "/", mustWork = TRUE) :
>   path[1]="fnord.shp": No such file or directory
> 
> "No such file or directory"
> 
> Barry
> 
> 
> 
> On Fri, Jan 22, 2016 at 2:25 AM, boB Rudis <bob at rudis.net> wrote:
>> Agreed with the others. After finding that shapefile and getting it to
>> work you are definitely not in the proper working directory.
>> 
>> On Thu, Jan 21, 2016 at 8:40 PM, David Winsemius <dwinsemius at comcast.net> wrote:
>>> 
>>>> On Jan 21, 2016, at 4:39 PM, Amoy Yang via R-help <r-help at r-project.org> wrote:
>>>> 
>>>> Any advice for the following errors?
>>>> state.map <- readShapeSpatial("maps/st24_d00.shp")
>>>> Error in getinfo.shape(fn) : Error opening SHP file
>>> 
>>> What does list.files('maps') return? Is there a 'st24_d00.shp' value in there?
>>> 
>>> 
>>> --
>>> David.
>>> 
>>>> 
> 
> 
> 
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David Winsemius
Alameda, CA, USA