Stephane Dray <dray <at> biomserv.univ-lyon1.fr> writes: : : Hello, : I have search on R website but do not find any solution. : I would like to know if R has some functionalities to produce analytical results : of equation. or more generally if it contains some functions to simplify equation. : : For example: : I would like to obtain x1 from: : x1+x2=8 (x1=8-x2) : : x1^2+x2=8 (x1=sqrt(8-x2)) : : Is is possible in R ? if not, do you know a (free) software that could do the job ?
I don't think R has this capability built in but you could try a computer algebra system. Yacas (http://yacas.sourceforge.net) as well as a number of others are free. Here is your calculation in yacas: C:\yacas>yacas True; This is Yacas version '1.0.54'. Yacas is Free Software--Free as in Freedom--so you can redistribute Yacas or modify it under certain conditions. Yacas comes with ABSOLUTELY NO WARRANTY. See the GNU General Public License (GPL) for the full conditions. See http://yacas.sf.net for more information and documentation on Yacas. Numeric mode: "Internal" To exit Yacas, enter Exit(); or quit or Ctrl-c. Type ?? for help. Or type ?function for help on a function. Type 'restart' to restart Yacas. To see example commands, keep typing Example(); In> Solve(x1+x2==8,x1); Out> 8-x2; In> Solve(x1^2+x2==8,x1); Out> (8-x2)^(1/2); ______________________________________________ [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