Message-ID: <CALsJ7pR1NDMyQk5mWN09srXs7di3xkwhsnsSdybrGikPhUZ7iw@mail.gmail.com>
Date: 2016-02-22T18:19:41Z
From: Agus Camacho
Subject: adapting spatial points and wrld_smpl to a reference system implicit in a .nc file
In-Reply-To: <56CB4DA6.1080502@wildintellect.com>
Thanks Alex, but the locations still fall in the sea when i plot them using
your recommended Solution. I looked at the sites you proposed and they have
other values for lat_1, lat_0, etc..
2016-02-22 11:04 GMT-07:00 Alex M <tech_dev at wildintellect.com>:
> On 02/22/2016 09:50 AM, Agus Camacho wrote:
> > Dear all,
> >
> > Im trying to overlap these points:
> >
> https://www.dropbox.com/s/awdclg4cvsdngej/clean%20urosaurus%20records.csv?dl=0
> >
> > and a wrld_simpl object:
> > library(maptools)
> > data(wrld_simpl)
> >
> > Over this raster layer
> >
> https://www.dropbox.com/sh/qcw174tgogpnz7s/AAByDc3TeyFe3W4nEqTFix6Oa?dl=0
> >
> > This rastr comes from a .nc file without a reference system. The author
> of
> > that .nc file gave me the following data about the .nc.
> >
> > The projection is *Lambert conformal conic* projection
> > CEN_LAT = 38.0
> > CEN_LON = -100.0
> > TRUELAT1 = 25.
> > TRUELAT2 = 45.
> >
> > However, despite i have gone through many sites in the internet, i cant
> > figure it out:
> >
> > a) if that is all the data i need to set a reference system for my points
> > and the wrld_simp object.
> >
> > b) how to change a typical CRS object with such data
> >
> > Ex.CRS ("+proj=lcc+lat_0=38.0+lon0_2=-100+ellps=WGS84")
> >
> > Where do i enter the TRUELAT and CENLAT values?
> > Are there any site that explains easily what the fields in the CRS mean
> and
> > how to change them?
> >
> > Thanks in advance.
> >
>
> https://github.com/OSGeo/proj.4/wiki/GenParms
> https://trac.osgeo.org/proj/wiki/GenParms
>
> I believe:
> +lat_0 = CEN_LAT Latitude of origin
> +lat_1 = TRUELAT1 Latitude of first standard parallel
> +lat_2 = TRUELAT2 Latitude of second standard parallel
> +lon_0 = CEN_LON Central meridian
>
> proj strings are defined by the proj4 libary. It's website listed above
> and the associated mailing lists or gis stackexchange would be the
> places to get help on it.
> https://lists.osgeo.org/mailman/listinfo/metacrs
>
> It often helps to browse similar projections on
> http://spatialreference.org/
> http://epsg.io/
>
> Enjoy,
> Alex
>
>
--
Agust?n Camacho Guerrero.
Doutor em Zoologia.
Laborat?rio de Herpetologia, Departamento de Zoologia, Instituto de
Bioci?ncias, USP.
Rua do Mat?o, trav. 14, n? 321, Cidade Universit?ria,
S?o Paulo - SP, CEP: 05508-090, Brasil.
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