Dear Sueli, Assuming that your data is in a data frame called "mydata", something like the following should work:
# splitting the data by SAMPLE msp<-with(mydata,split(mydata,SAMPLE)) # linear models by sample models<-lapply(msp,function(x) lm(KA ~ PA, data = x)) # linear models by sample models<-lapply(msp,function(x) lm(KA ~ PA, data = x)) models # summaries lapply(models,summary) # to access the models for the first sample and plot its residuals par(mfrow=c(2,2)) plot(models[[1]]) # to access a different sample, change the number "1" HTH, Jorge On Fri, Mar 6, 2009 at 7:07 AM, Sueli Rodrigues <srodr...@esalq.usp.br>wrote: > > Hi, I have the following file, and I need to work out the linear > regression for each sample. I tried the model(*) and receive the error > message (**): > > data=split(mydata,rep(1:(nrow(mydata)/6),each=6)) > > arrang.linear=lapply(data,lm,formula=KA~PA) > Erro em storage.mode(y) <- "double" : > invalid to change the storage mode of a factor > Além disso: Warning message: > In model.response(mf, "numeric") : > using type="numeric" with a factor response will be ignored > > SAMPLE PA KA > 2 0.917 11.261 > 2 0.823 11.010 > 2 0.803 10.381 > 2 0.744 10.208 > 2 0.697 10.006 > 2 0.681 9.916 > 3 0.789 10.271 > 3 0.702 10.076 > 3 0.692 9.990 > 3 0.646 9.779 > 3 0.620 9.749 > 3 0.608 9.708 > 4 1.052 11.779 > 4 0.941 11.249 > 4 0.881 10.140 > 4 0.824 10.052 > 4 0.790 9.859 > . . . > . . . > . . . > 80 0.499 9.819 > > Sueli Rodrigues > > Eng. Agrônoma - UNESP > Mestranda - USP/ESALQ > PPG-Solos e Nutrição de Plantas > Fones (19)93442981 > (19)33719762 > > ______________________________________________ > 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. > [[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.
