[R-sig-Geo] adapting spatial points and wrld_smpl to a reference system implicit in a .nc file

[Agus Camacho]

but its ok, ill ask in another mail list.

2016-02-22 11:19 GMT-07:00 Agus Camacho <agus.camacho at gmail.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
>>
>>
>
>
> --
> Agustín Camacho Guerrero.
> Doutor em Zoologia.
> Laboratório de Herpetologia, Departamento de Zoologia, Instituto de
> Biociências, USP.
> Rua do Matão, trav. 14, nº 321, Cidade Universitária,
> São Paulo - SP, CEP: 05508-090, Brasil.
>



-- 
Agustín Camacho Guerrero.
Doutor em Zoologia.
Laboratório de Herpetologia, Departamento de Zoologia, Instituto de
Biociências, USP.
Rua do Matão, trav. 14, nº 321, Cidade Universitária,
São Paulo - SP, CEP: 05508-090, Brasil.

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