R devel - Aug 1997 - R-alpha: Matrix Class

The have been a few prods to create an S-like matrix class for R.  A
major reason for having a matrix class seems to be that people get
bitten by the default behavior of the drop= parameter to "[".  That
being the case does it make sense to change the semantics of "["
rather than introducing a new class?

I'm just wondering because I'm in a "smaller is better" kind
of mood
after having been delving into the "lm" code and thinking about how
big R is becoming ...
	Ross
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On Tue, 12 Aug 1997, Ross Ihaka wrote:
> The have been a few prods to create an S-like matrix class for R.  A
> major reason for having a matrix class seems to be that people get
> bitten by the default behavior of the drop= parameter to "[". 
That
> being the case does it make sense to change the semantics of "["
> rather than introducing a new class?
I think changing the semantics is preferable, in part because it fixes the
drop problem automatically, rather than requiring everyone to use a new
feature.  Creating a Matrix class would not fix the array problem for
arrays of dimension 3 or more, either.

However, a Matrix library might be a nice place to put matrix features
that not everyone needs. This helps keep the size of R down.  Libraries
that can be loaded and unloaded seem like the ideal place to put a whole
lot of things, rather than taking the S-PLUS approach of bundling gam and
trees and nlme and everything else together.  


Thomas Lumley
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Ross

If you're looking at the drop= code it sure would be nice to be able to
(optionally) supply a vector (eg. drop=c(F,F,T) ) for higer dimension arrays.

Paul Gilbert
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