[R] Converting Geo-Coordinates Unities

[Roger Bivand]

Rodrigo Aluizio <r.aluizio <at> gmail.com> writes:

> 
> Thanks for the elucidation James.
> After reading the .pdf of proj4 and your answer, I believe I won't need 
> proj4 package.
> Well, I still don't know all the kind of transformations we will need here. 
> I'm just getting prepared to future data that is arriving soon.
> Each time they come, there is a different coordinate unit...
> I'll star elaborating the mathematic functions for conversions, and save 
> them in a safe place!
> Anyway thank you so much!

First, visit the Task Views page on CRAN, and find the Spatial task view. There 
you will find effectively all you need. Look in the sp package documentation for 
the DMS class for conversion of decimal degrees to DDD:MM:SS, it may help.

Do look at PBSmapping or rgdal (project(), spTransform()) for projection to UTM 
and other coordinate reference systems. Both the mapproj and proj4 packages can 
be used, but neither is convenient to use if the output needs to be kept 
portable. 

Task Views answer quite a lot of questions!

Roger

> 
> Rodrigo.
>