---Chris Burke wrote: > Sherlock, Ric wrote: > > I have been investigating interfacing J and R using Rserve. > > <http://www.jsoftware.com/jwiki/Interfaces/R/Rserve> > > > > I am interested in how best to go about working with the > Attribute lists > > returned by the interface. > > When I first looked at this, I stopped here, because I was > not sure of > the exact representation of attributes. I had expected them > to be a pair: > > value;`name > > where `name is the attribute name, and value is the value, > which itself > may be an attribute or attribute list. > > Your first example matches this. The second example does not, > since the > attribute is a 3 item list. > > Do you know of an exact definition of attributes?
Having a brief look at this under XP where the structures work OK, it looks something like this to me: If Rget returns a structure rather than simple data, it is in the form of a 2 item boxed list, the 1st box contains the attributes of the data in the 2nd box. The box containing the attributes contains a list of 2 or 3 boxed items. The last item contains the attribute name and the first one contains the attribute value(s). If a middle boxed item exists, it is also a list of 2 or 3 boxed items, the last is the attribute name, the first is the value and the middle one if it exists is a 2 or 3 item boxed list ... etc. These commands seem to produce structures that conform to the above description. Rget 'cars' Rget 'OrchardSprays' Rget 'lm(dist ~ speed, data=cars)' A portion of the structure produced by the last command seems to be an exception though which suggests that my description above is not completely accurate. Rget '(lm(dist ~ speed, data=cars)$qr)$qr' ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
