Hi all,



Prefix: I am a frustrated Java coder in R.



I am coding a medium sized ecosystem modelling program in R.  I have changed to using S4 objects and it has cost me an order of magnitude in execution speed over the functional model.  I cannot afford this penalty and have found that it is the result of all the passing-by-value of objects.



I see that you can now safely inherit from environment in V2.9.0.

That got me all excited that I would now be able to pass objects by reference.



But...

That doesn't seem to be the case.

It only seem that passing an environment which holds the object allows for pass-by-reference and that passing an object which inherits from environment doesn't.

Why is this the case, either an object inherits the properties of its parent or it doesn't.

Has anyone else had a play with this?  Or have I got it all wrong.



I tried the below:

-----------------------------------------------------------------------------------------

setClass('foo', representation=representation(stuff='list', bar='numeric'),

                     prototype=list(stuff=list(), bar=0),

                     contains='.environment')



setGeneric('doit', function(.Object, newfoo='environment') standardGeneric('doit'))



setMethod('doit', 'foo', function(.Object, newfoo){newfoo@bar <- 10})



z <- new('foo')



z@stuff$x <- new('foo')



doit(z,z@stuff$x)



z@stuff$x@bar



[1] 0

------------------------------------------------------------------------------------------



Can anyone help with a better way of doing this.

I'm trying to avoid all the indirection of packing and unpacking environments for passing.





Thanks heaps



Troy





Troy Robertson

Database and Computing Support Provider

Southern Ocean Ecosystems, ERM/Fish

Australian Antarctic Division

Channel Highway, Kingston 7050

PH: 03 62323571

Troy.Robertson@aad.gov.au




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