[Gvsig_english] computing area

César Martínez Izquierdo cesar.izq at gmail.com
Fri Feb 27 14:20:06 CET 2009


I think you set the CRS of the layer, but you forgot to set it for the view.
You should set EPSG:4326 both for the view and the layer.

Regards,

   César

Nik Go escribió:
> Its  EPSG:23030 though normally it should be WGS84 / EPSG4326 but if I 
> don't change the projection, I cannot edit the shapefile.
> I get the following error message:
> 
>     no es posible editar capa reproyectada, para editaria primero
>     utilliza el geoproceseso de reproyektar
> 
> 
>  
> On Thu, Feb 26, 2009 at 5:23 PM, Benjamin Ducke 
> <benjamin.ducke at oxfordarch.co.uk 
> <mailto:benjamin.ducke at oxfordarch.co.uk>> wrote:
> 
>     So what spatial reference system is your view using?
>     Cartesian? Latitude/longitude? EPSG Code?
> 
>     Ben
> 
>     Nik Go wrote:
> 
>         I'm sorry for the completing the details. Here they are:
> 
>         gvSIG version: 1.9a build 1226
>         gvSIG OAD edition based on v 1.1.2
>         OS - 64 bit Ubuntu 8.04
> 
>         Surprisingly, the numbers returned by both versions are the
>         same. The project properties has been set to km^2 already and I
>         made no re-projections. (Should I?) There were no internal
>         polygons in the feature I tested.
> 
>         Excuse me if these question seems basic, I'm still learning new
>         things about GIS in gvSIG.
> 
>         Salud,
>         Nik
> 
> 
> 
> 
>         2009/2/25 Cesar Martinez Izquierdo <cesar.martinez at iver.es
>         <mailto:cesar.martinez at iver.es> <mailto:cesar.martinez at iver.es
>         <mailto:cesar.martinez at iver.es>>>
> 
> 
>            Hello Nik,
> 
>            It is necessary that you provide some details when you report a
>            problem, otherwise it's impossible to find the problem.
> 
>            Which version of gvSIG are you using?
>            Which CRS have set in the view? And in the layer? Which
>         measurement
>            units did you set?
> 
>            Regards,
> 
>             César
> 
>            Nik Go escribió:
> 
>                I'm trying to determine the total area of features but the
>                area() function of the field calculator are returning numbers
>                that are off the real-world sizes. I have real-world
>         numbers for
>                comparison. (Calculator returns 0.122893 km^2 when the actual
>                size is 1,483.38 km^2 )
> 
> 
>                Am I doing anything wrong?
> 
> 
>              
>          ------------------------------------------------------------------------
> 
>                _______________________________________________
>                Gvsig_internacional mailing list
>                Gvsig_internacional at runas.cap.gva.es
>         <mailto:Gvsig_internacional at runas.cap.gva.es>
>                <mailto:Gvsig_internacional at runas.cap.gva.es
>         <mailto:Gvsig_internacional at runas.cap.gva.es>>
> 
>                http://runas.cap.gva.es/mailman/listinfo/gvsig_internacional
> 
> 
> 
>            --    César Martínez Izquierdo
>            Equipo de desarrollo gvSIG
>            http://www.gvsig.org/web/
> 
>            IVER T.I.
>            C/ Lérida, 20
>            46009 Valencia - Spain
>            http://www.iver.es
> 
> 
>            Este mensaje y sus archivos son confidenciales. No está
>         permitida su
>            reproducción o distribución sin la autorización expresa de "IVER
>            Tecnologías de la Información". Si usted no es el destinatario
>            previsto, queda desautorizado cualquier uso, acceso o copia
>         de este
>            mensaje. Si ha recibido este mensaje por error, por favor
>         bórrelo e
>            infórmenos por esta misma vía.
> 
> 
>            _______________________________________________
>            Gvsig_internacional mailing list
>            Gvsig_internacional at runas.cap.gva.es
>         <mailto:Gvsig_internacional at runas.cap.gva.es>
>            <mailto:Gvsig_internacional at runas.cap.gva.es
>         <mailto:Gvsig_internacional at runas.cap.gva.es>>
> 
>            http://runas.cap.gva.es/mailman/listinfo/gvsig_internacional
> 
> 
> 
>         ------------------------------------------------------------------------
> 
>         _______________________________________________
>         Gvsig_internacional mailing list
>         Gvsig_internacional at runas.cap.gva.es
>         <mailto:Gvsig_internacional at runas.cap.gva.es>
>         http://runas.cap.gva.es/mailman/listinfo/gvsig_internacional
> 
> 
> 
>     -- 
>     Benjamin Ducke
>     Senior Applications Support and Development Officer
> 
>     Oxford Archaeology Ltd
>     Janus House
>     Osney Mead
>     OX2 0ES
>     Oxford, U.K.
> 
>     Tel: +44 (0)1865 263 800 (switchboard)
>     Tel: +44 (0)1865 980 758 (direct)
>     Fax :+44 (0)1865 793 496
>     benjamin.ducke at oxfordarch.co.uk <mailto:benjamin.ducke at oxfordarch.co.uk>
> 
> 
> 
> 
>     ------
>     Files attached to this email may be in ISO 26300 format (OASIS Open
>     Document Format). If you have difficulty opening them, please visit
>     http://iso26300.info for more information.
> 
> 
>     _______________________________________________
>     Gvsig_internacional mailing list
>     Gvsig_internacional at runas.cap.gva.es
>     <mailto:Gvsig_internacional at runas.cap.gva.es>
>     http://runas.cap.gva.es/mailman/listinfo/gvsig_internacional
> 
> 
> 
> ------------------------------------------------------------------------
> 
> _______________________________________________
> Gvsig_internacional mailing list
> Gvsig_internacional at runas.cap.gva.es
> http://runas.cap.gva.es/mailman/listinfo/gvsig_internacional


-- 
César Martínez Izquierdo
Equipo de desarrollo gvSIG
http://www.gvsig.org/web/

IVER T.I.
C/ Lérida, 20
46009 Valencia - Spain
http://www.iver.es


More information about the Gvsig_internacional mailing list