On 7/15/05, simon blomberg <[EMAIL PROTECTED]> wrote: > > > >>>>> "bry" == bry <[EMAIL PROTECTED]> > > >>>>>> on Fri, 15 Jul 2005 14:16:46 +0200 writes: > > > > > > bry> About a year ago there was a discussion about interfacing R > > >with J on the J > > > bry> forum, the best method seemed to be that outlined in this > > >vector article > > > bry> http://www.vector.org.uk/archive/v194/finn194.htm > > > > > >(which is interesting to see for me, > > > if I had known that my posted functions would make it to an APL > > > workshop... > > > BTW: Does one need special plugins / fonts to properly view > > > the APL symbols ? ) > > > > > > > > > bry> and use J instead of APL > > > > > > bry> http://www.jsoftware.com > > > > > >well, I've learned about J as the ASCII-variant of APL, and APL > > >used to be my first `beloved' computer language (in high school!) > > >-- but does J really provide computer algebra in the sense of > > >Maxima , Maple or yacas... ?? > > > > I wonder if at this point it would be useful to think about how a > > symbolic algebra system might be used by R users, and whether that > > would affect the choice of system. For example, Maxima and yacas seem > > to be mostly concerned with "getting the job done", which might be > > all that the data analyst or occasional user needs. However, > > mathematical statisticians might be more concerned with developing > > new mathematics. For example, commutative algebra has been found to > > be very useful in the theory of experimental design (e.g. Pistone, > > Riccomagno, Wynn (2000) Algebraic Statistics: Computational > > Commutative Algebra in Statistics. Chapman & Hall). Now, Maxima can > > already do the necessary calculations (ie Groebner bases of > > polynomials), but as far as I know, yacas cannot. But who knows where >
yacas does have the Groebner function, e.g. In> Groebner({x*(y-1),y*(x-1)}) Out> {x*y-x,x*y-y,y-x,y^2-y}; ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel