On Fri, Oct 22, 2010 at 7:20 AM, Manuel SpÃnola <mspinol...@gmail.com>wrote:
> Thank you Michael,
>
> The second shapefile doesn't have a .prj file. Is that a problem.
> Can I make one with the file from the first shapefile.
> Best,
>
>
Yes, that will work fine - but you really should check that the .prj
contents is appropriate for both data sets.
Cheers, Mike.
> Manuel
>
> 2010/10/21 Michael Sumner <mdsum...@gmail.com>
>
> Presumably there was valid coordinate system metadata for the first
>> "corr", but not the second.
>>
>> See
>>
>> proj4string(corr)
>>
>> If the data is longlat on WGS84 you can override the missing (NA)
>> coordinate system with something like this before using spTransform:
>>
>> proj4string(corr) <- CRS("+proj=longlat +ellps=WGS84")
>>
>> but you should check carefully with the source of the data to ensure that
>> PROJ.4 string is appropriate - using the same as that reported by the first
>> data set may be right.
>>
>> Cheers, Mike.
>> On Fri, Oct 22, 2010 at 6:45 AM, Manuel SpÃnola
>> <mspinol...@gmail.com>wrote:
>>
>>> Dear list members,
>>>
>>> I am trying to project some shapefiles with function spTransform but I
>>> got
>>> an error.
>>>
>>> My first shapefile was ok
>>>
>>> > corr = readOGR(dsn="C:/ProyectoRespacial/EvalHab_reporte",
>>> layer="corredor05unico") # en coordenadas geográficas
>>> > corr.transf = spTransform(corr, CRS("+proj=tmerc +lon_0=-84 +lat_0=0
>>> +k=0.9999 +datum=WGS84")) # para CRTM05
>>> > writeOGR(corr.transf,
>>> dsn="C:/ProyectoRespacial/CBSS/Shapefiles_proyectados",
>>> layer="corredorCRTM05", driver="ESRI Shapefile") # para escribir el shape
>>> > corr = readOGR(dsn="C:/ProyectoRespacial/CBSS/Shapefiles_proyectados",
>>> layer="corredorCRTM05")
>>> OGR data source with driver: ESRI Shapefile
>>> Source: "C:/ProyectoRespacial/CBSS/Shapefiles_proyectados", layer:
>>> "corredorCRTM05"
>>> with 1 features and 4 fields
>>> Feature type: wkbPolygon with 2 dimensions
>>> > plot(corr, axes=TRUE)
>>>
>>> but my second gave me an error.
>>>
>>> > cob = readOGR(dsn="C:/ProyectoRespacial/CBSS/LAINcambios",
>>> layer="coberturascsls2006_cr05") # en coordenadas geográficas
>>> OGR data source with driver: ESRI Shapefile
>>> Source: "C:/ProyectoRespacial/CBSS/LAINcambios", layer:
>>> "coberturascsls2006_cr05"
>>> with 6016 features and 3 fields
>>> Feature type: wkbPolygon with 2 dimensions
>>> > cob.transf = spTransform(cob, CRS("+proj=tmerc +lon_0=-84 +lat_0=0
>>> +k=0.9999 +datum=WGS84")) # para CRTM05
>>> Error en spTransform(xSP, CRSobj) :
>>> No transformation possible from NA reference system
>>>
>>> Best,
>>>
>>> Manuel
>>>
>>> [[alternative HTML version deleted]]
>>>
>>>
>>> _______________________________________________
>>> R-sig-Geo mailing list
>>> R-sig-Geo@stat.math.ethz.ch
>>> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>>>
>>>
>>
>>
>> --
>> Michael Sumner
>> Institute for Marine and Antarctic Studies, University of Tasmania
>> Hobart, Australia
>> e-mail: mdsum...@gmail.com
>>
>
>
--
Michael Sumner
Institute for Marine and Antarctic Studies, University of Tasmania
Hobart, Australia
e-mail: mdsum...@gmail.com
[[alternative HTML version deleted]]
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