Dear Erin, Not exactly elegant, but
> e<-expression(list(R == 100 * (1 - 2 * y/10000))) > ee <- e[[1]][2] > ee (R == 100 * (1 - 2 * y/10000))() > eval(parse(text=(substring(paste(ee), 5))), list(y=5)) [1] 99.9 Regards Søren -----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Erin Hodgess Sent: 19. juni 2013 07:03 To: R help Subject: [R] evaluation of equations from Ryacas Hello again. Now I have the following: > xx [1] "Solve(1 - R/100==(2*y)/10000,R)" > yacas(xx) expression(list(R == 100 * (1 - 2 * y/10000))) > I would like to put in a value for y and obtain R. I've tried more stuff with eval and Eval, but no luck yet. Any suggestions would be much appreciated. Thanks, Erin -- Erin Hodgess Associate Professor Department of Computer and Mathematical Sciences University of Houston - Downtown mailto: erinm.hodg...@gmail.com [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org 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@r-project.org 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.
