On Thu, 2003-10-02 at 10:25, Rajarshi Guha wrote: > Hi, > I am trying to build a series of rlm models. I have my data frame and > the models will be built using various coulmns of the data frame. > > Thus a series of models would be > > m1 <- rlm(V1 ~ V2 + V3 + V4, data) > m2 <- rlm(V1 ~ V2 + V5 + V7, data) > m3 <- rlm(V1 ~ V2 + V8 + V9, data) > > I would like to automate this. Is it possible to use a string in place > of the formula? > > I tried doing: > > fmla <- sprintf('V1 ~ V%g + V%g + V%g',2,3,4) > m1 <-rlm(fmla,data) > > I get: > > Error in qr(x) : NA/NaN/Inf in foreign function call (arg 1) > In addition: Warning message: > NAs introduced by coercion > > I can understand why this method results in the error but is there any > way to get around this? >
See ?as.formula You can then construct an expression and use something like: m1 <- rlm(as.formula(expression), data) HTH, Marc Schwartz ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help