Dear R helpers: I am a R novice and have a question about using table() to extract frequences over many sub-datasets. A small example input dataframe and wanted output dataframe are provided below. The real data is very large so a for loop is what I try to avoid.
Can someone englithen me how to use sapply or the like to achieve it? Many thanks in advance! -Sean #example input dataframe id <- c('tom', 'tom', 'tom', 'jack', 'jack', 'jack', 'jack') var_interest <- c("happy","unhappy", "", "happy", "unhappy", 'soso','happy') input.df <- data.frame(id=id, var_interest=var_interest) input.df wanted.df <- #output dataframe I want id_unique <- c('tom','jack') happy_freq<-c(1,2) unhappy_freq<-c(1,1) soso_freq<-c(0,1) miss_freq<-c(1,0) output.df <-data.frame(id_unique=id_unique, happy_freq=happy_freq, unhappy_freq=unhappy_freq, soso_freq=soso_freq, miss_freq=miss_freq) output.df [[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.