Here is a slightly shorter way to do it although it involves passing a yacas string directly:
> yacas("a * Identity(3)") expression(list(list(a, 0, 0), list(0, a, 0), list(0, 0, a))) > PrettyForm("%") / \ | ( a ) ( 0 ) ( 0 ) | | | | ( 0 ) ( a ) ( 0 ) | | | | ( 0 ) ( 0 ) ( a ) | \ / On 10/16/06, Gabor Grothendieck <[EMAIL PROTECTED]> wrote: > Its pretty limited right now but you can do this: > > > library(Ryacas) > > d <- List(List(1, 0, 0), List(0, 1, 0), List(0, 0, 1)) > > a <- Sym("a") > > a * d > expression(list(list(a, 0, 0), list(0, a, 0), list(0, 0, a))) > > PrettyForm("%") > / \ > | ( a ) ( 0 ) ( 0 ) | > | | > | ( 0 ) ( a ) ( 0 ) | > | | > | ( 0 ) ( 0 ) ( a ) | > \ / > > The ASCII representation of the matrix will look correct in R although its > possible that the email process munges it up so it may not look right > when you receive this. > > Also there are also matrix examples on the home page, in the Ryacas vignette > and in the Ryacas-Sym vignette. > > Note that by mistake the vignette labelled Ryacas-Sym in the package > itself is actually a copy of the Ryacas vignette so to see the actual > Ryacas-Sym vignette currently one must look at the one in the source > repository: > http://ryacas.googlecode.com/svn/trunk/inst/doc/Ryacas-Sym.pdf > > > > On 10/16/06, Cleber N. Borges <[EMAIL PROTECTED]> wrote: > > Hello, > > > > First, > > I would like to congratulations for very cool package! It's very > > nice > > idea!... > > Secondly, > > Is there a way to send R'objects (variables) to yacas and make > > symbolic > > operations?? > > for example: > > > > d <- diag(3) > > a <- "A" > > > > yacas( d * a ) > > > > Thanks, > > Cleber Borges > > > > > > Gabor Grothendieck wrote: > > > > >Ryacas is an R interface to the free yacas computer algebra > > >system. Ryacas allows one to send R expressions, > > >unprocessed yacas strings and certain other R objects to a > > >separate yacas process from R and get back the result. It > > >also has facilities for manipulating yacas strings and R > > >expressions destined for yacas processing. > > > > > >It can be used for exact arithmetic, symbolic math, ASCII > > >pretty printing and translating R to TeX. > > > > > > > > >Online info. For overview, pointers to additional > > >information, installation instructions and a sample session > > >see: > > > > > > http://code.google.com/p/ryacas/ > > > > > >The vignettes can be viewed online here: > > > > > > http://ryacas.googlecode.com/svn/trunk/inst/doc/Ryacas.pdf > > > http://ryacas.googlecode.com/svn/trunk/inst/doc/Ryacas-Sym.pdf > > > > > > > > >More. Once Ryacas is installed, pointers to additional > > >information can be found with these R commands: > > > > > > library(Ryacas) > > > package?Ryacas > > > > > > > > >--- > > > > > > > > > > ______________________________________________ > > R-help@stat.math.ethz.ch mailing list > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > > and provide commented, minimal, self-contained, reproducible code. > > > ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.