Question

I am working with data.frames that have very similar names (df1, df2,.. df7). Because most of the analysis will be done in all, I would like to automatize the process as much as possible. I have already managed to use assign when reading the files:

for(i in 1:7) { 
  NameFile <- paste("df",i,"_10/score.out", sep="")
  OutFile <- read.table(NameFile, na.string="NA",header=TRUE,sep="\t")
  NameVar <- paste("df",i,"_10", sep="")
  assign(NameVar, OutFile)
  }

But now I would also like to perform the operation/function also in all of them. For instance subsetting:

for(i in 1:7) {
              Newname <- paste("dfsmall",i,sep="")
              dftemp <- subset(df[i], p == 0   & abs(sepscore) > 0.3)
              assign(Newname, dftemp)
              }

I think most of the is correct but how do I call df[i]? That is, the objects that already exist with the names df1, df2(..)? And is there a cleaner way to do this?

There are a few similarish questions here, but none that would find suitable for my problem. Then again, I am prone to missing the obvious.

Thanks.

Answer 1

By using function get (work the same as assign but in reverse):

 for(i in 1:7) {
          get(paste("df",i,"_10",sep="")) -> df
          Newname <- paste("dfsmall",i,sep="")
          dftemp <- subset(df, p == 0   & abs(sepscore) > 0.3)
          assign(Newname, dftemp)
          }