Re: [R] subset data right

>If you want to drop levels, use droplevels() either on the factor or on the >subset of your data frame. Example: >droplevels(f[1]) #One element, only one level Calling factor() on a factor, as the OP did, also drops any unused levels, as the examples showed. >

Re: [R] subset data right

> You did not change df$quant - you made a new object called 'subdf' > containing a column called 'quant' that had only one level. Changing subdf > has > no effect on df. Also, subsetting a factor _intentionally_ does not change the number of levels. Example: f <- factor(sample(letters[1:3],

Re: [R] subset data right

You did not change df$quant - you made a new object called 'subdf' containing a column called 'quant' that had only one level. Changing subdf has no effect on df. > df <- data.frame(quant=factor(letters)) > str(df) 'data.frame': 26 obs. of 1 variable: $ quant: Factor w/ 26 levels

Re: [R] subset data right

Hello, Don't use subset, use indexing. subdf <- df[df$quant %in% "VeryFast", ] By the way, instead of %in% you can use ==, since you're interested in just one value of quant. Hope this helps, Rui Barradas Citando ch.elahe via R-help : > Hi all, > I have the following

[R] subset data right

Hi all, I have the following df and I want to know which Protocols are VeryFast, which are FAST, which are SLOW and also which ones are VerySLOW : $ Protocol : Factor w/ 48 levels "DP FS QTSE SAG",..: 5 5 28 5 5 5 7 7 47 5 ... $ quant : Factor w/ 4 levels