[R] General function to substitute values in a data frame

Hi R users, I need a way to substitute the values 10:31 to the letters A:V (i.e 10=A, 11=B, ..., 31=V) in a data frame. For example: > y<-c(10,11,12,13) > z<-c(28,29,30,31) > df<-data.frame(y,z) > df y z 1 10 28 2 11 29 3 12 30 4 13 31 Then I would substitute it and obtain a data frame like

[R] CCA - manual selection

Hello, I am trying to obtain f-values for response (independent) variables from a CCA performed in vegan package, to see which ones of them have significative influence in my dependent variables (like the manual selection in canoco), but I can't find any function (or package) that do such a thing