Hi, I try to use a substitute function to generalise a equation.
I have this: expression(1+2*pred+3*lat) I need to define the equation in function of x1 and x2 variables. Also I try to define who is x1 and x2. I try this: X1 <- "pred" X2 <- "lat" Now I need substitute pred and lat in equation by x1 and x2 defined on X1 and X2 above, I try this way: > substitute(expression(1+2*pred+3*lat),list(as.name(X1)=as.name(x1),as.name(X2)=as.name(x2)) Error: unexpected '=' in "substitute(expression(1+2*pred+3*lat),list(as.name(X1)=" My expected result is: expression(1 + 2 * x1 + 3 * x2) Any help? Thanks Ronaldo -- > Prof. Ronaldo Reis Júnior | .''`. UNIMONTES/Depto. Biologia Geral/Lab. de Biologia Computacional | : :' : Campus Universitário Prof. Darcy Ribeiro, Vila Mauricéia | `. `'` CP: 126, CEP: 39401-089, Montes Claros - MG - Brasil | `- Fone: (38) 3229-8187 | [EMAIL PROTECTED] | [EMAIL PROTECTED] | http://www.ppgcb.unimontes.br/ | ICQ#: 5692561 | LinuxUser#: 205366 ______________________________________________ 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.