Dear R Help team, I'm having some problems running a discriminant analysis (MASS:lda) over my data, i have a grouping variable coming from a previous cluster analysis and several discriminators (78 actually). I'm trying to run lda using column index as independent variable in the formula like it's done in the help page for ?formula:
>lda(Grupo~paste(names(cien[,3:80]),collapse="+"),data=cien) but i get the following error: Error in model.frame.default(formula = Grupo ~ paste(names(cien[, 3:80]), : different variable length (found in 'paste(names(cien[, 3:80]), collapse = "+")') (This is my english translation of the error msg while i use R in spanish so it should look different in your machines) The funny thing is that if i use: >paste(names(cien[,3:80]),collapse="+") [1] "X.SO.M2+X.SO.M4+X.SO.M6+X.SO.M8+X.SO.M10+X.SO.M12+..... and then copy and paste the result in the formula: > lda(Grupo~X.SO.M2+X.SO.M4+X.SO.M6+X.SO.M8+X.SO.M10+X.SO.M12+....,data=cien) then there's no error!!! the lda runs just fine. I know i might be doing something wrong but i don't know where so could you please enlighten me? Thanks in advance PD. Here's a piece of the data: NOMEST Grupo X.SO.M2 X.SO.M4 X.SO.M6 X.SO.M8 .....(78 var) 1 Ciénaga La Ahuyama 3 95.1 152.3 115.3 97.6 2 Boca del Caño Grande 3 91.0 104.2 131.7 89.4 3 Buenavista 3 115.6 102.9 122.0 110.5 4 Ciénaga El Loro 1 104.0 80.9 68.5 50.7 . . . -- Marcos Antonio Carvajalino Fernández Estudiante de Ingeniería Ambiental y Sanitaria Universidad del Magdalena Santa Marta, Colombia ______________________________________________ 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.