On Tue, 20 Jan 2004 19:42:51 +0000 (GMT), Prof Brian Ripley <[EMAIL PROTECTED]> wrote :
>On Tue, 20 Jan 2004, Roger D. Peng wrote: > >> Obviously, it was data.restore() that produced the error >> below. However, I think S-PLUS 5 might not be supported by >> data.restore() in the `foreign' package since the docs there >> say it can only read objects from S-PLUS versions 3.x and >> 4.x (on Unix). > >Correct. We don't have a description of the S4 (hence S-PLUS 5.x and 6.x) >data.dump format. We recommend using data.dump(oldStyle=T) in those >versions of S-PLUS if possible. I developed the data.restore code that's there by recognizing that the data.dump output was closely related to the binary format, which I had reverse-engineered several years before. I imagine there are a couple of possibilities to update it to the newer format: 1. We could approach Insightful, and find out if they'd give us specs for the format. They might be published somewhere, or they might be willing to let us base our implementation on their data.restore function. This would need someone who knows who to contact at Insightful so as to maximize the probability of a positive response. 2. We could reverse engineer the format. This is probably easier than you'd think. It's just a matter of creating instances of all of the kinds of objects that you want to be able to read, and seeing what the dump looks like, and then trying out the procedure on a larger body of data, and iterating a few times. It's hopeless to think that many complex objects will ever be recoverable this way (the internals of R are different than S-PLUS), but it shouldn't be too hard to get vectors and data.frames, and maybe functions. Duncan Murdoch ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
