Hey Marcio,

There is a JuliaGeo organization <https://github.com/JuliaGeo/>, and we'll 
be happy to have you help out!

>From what I see, the data field of the Raster object loads the raster to 
memory, rather than keeping a reference to the values. This is up for debate 
<https://github.com/wkearn/RasterIO.jl/issues/3#issue-55769745> though, and 
maintaining a handle to the underlying raster might be a more viable 
approach (which is the approach taken in LibGEOS.jl 
<https://github.com/JuliaGeo/LibGEOS.jl> and Proj4.jl 
<https://github.com/FugroRoames/Proj4.jl>).

To mimic matrix indexing, you implement the getindex method (read the section 
on Arrays in the julia manual 
<http://julia.readthedocs.org/en/latest/manual/arrays/>). And no, you do 
have to manually make calls to destroy the raster objects you maintain a 
handle to; they probably have it documented in their C API, the gc does not 
do that for you.

There is also a julia-geo mailing list, where we'll be happy to entertain 
discussions on packages for geospatial libraries in julia. Shall we migrate 
this discussion there?

On Wednesday, 2 September 2015 00:03:28 UTC-4, Marcio Sales wrote:
>
> Hello all
> As a statistician and GIS practitioner, of course I'm interested in that 
> package. I've made a fork and started to play with the GDal functions, and 
> now I'm in condition to start contributing. As a start, I've made a 
> function to reproject a raster, with a choice to save a new file to disk or 
> just return the result as a new Raster object.
>
> I have a question about the Raster object though. It has a Data field that 
> I'm not sure if it loads the raster to the memory or just keeps a reference 
> to the values.
>
> I would prefer to keep just the reference and then tried to redefine the 
> raster type to have a gdaldataset field that keeps the handle to the 
> dataset. This way, I could write other functions to fetch data and keep 
> just the data I need in memory.
>
> However, as this reference is returned by a C function, I wonder what 
> happens to it when I delete or replace the value of the raster object 
> created. Is the reference destroyed automatically? I tried to use the 
> finalize function but it didnt work.
>
> Also, is there a way to write a function that mimics matrix indexing, like 
> making raster[i,j] invoke a GDAL function to fetch the values at i,j?
>
> Also, two suggestion to the owners:
> a) a constructor to Raster(filename) instead of the openraster function 
> (if this is possible)
> b) what about naming the package "JDAL.jl"?
>
>  
>
>

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