Unique combinations of all variables
问题 I have attempted to use the following code to come up with a table of unique combinations of a bunch of variables. V1=as.vector(CRmarch30[1]) V2=as.vector(CRmarch30[2]) V3=as.vector(CRmarch30[3]) V4=as.vector(CRmarch30[4]) V5=as.vector(CRmarch30[5]) V6=as.vector(CRmarch30[6]) V7=as.vector(CRmarch30[7]) As you may have already guessed, CRmarch30 is a dataframe with 7 columns. I converted each column into a vector. Then, i used the following code to create all unique combination of the 7