文件中的错误（文件，ifelse（追加，“a”，“w”））：无效的“描述”参数

Question

I am trying to create a function that takes a data frame of, at least, 100 variables and slice it so I can end up with multiple dfs that always contains the first 5 variables and then 10 of the remaining variables and then write the generated slice. Example of what I want to automate:

First_slice <- df1[,c(1:5, 6:15)]
Second_slice <- df1[,c(1:5, 16:25)]

My function

Auto.Slice <- function(df, base= 'slice'){
  x <- seq(6, 194, 10) #vector with the starts of my slices
  #print(x)
  #View(df)
  One.Slice <- function(df1, x=NULL, base){
    #View(df1)
    y <- if (x+9 <= ncol(df1)) x+9 else ncol(df1)
    #print(y)
    df2 <- df1[,c(1:5, x:y)]
    #View(df2)
    #print(base)
    file_name <- paste(base, x,'_', y, '.csv', sep ='')
    #print(file_name)
    write.table(df2, file_name, row.names = F, sep='\t', col.names = T)
  }
  One.Slice(df, x, base)
}

Auto.Slice(df = MS)

In order to identify the mistake I added several 'print' statements and I found out that the problem is when I want to write each slice into a.csv.

I have not found an answer to solve this. And interestingly, when I have the write statement out it works.

Error message

Error in file(file, ifelse(append, "a", "w")): invalid 'description' argument

Answer 1

Okey, never mind, I realized that the variable 'file_name' is a character vector which contains all the names of my slices. To solve this I used a for loop.

Auto.Slice <- function(df, base= 'slice'){
  x <- seq(6, 194, 10) #vector with the starts of my slices

  One.Slice<-function(df1, x=NULL, base){
    y <- if (x+9 <= ncol(df1)) x+9 else ncol(df1)
    df2 <- df1[,c(1:5, x:y)]
    file_name <- paste(base, x,'_', y, '.csv', sep ='')
    
    for (i in file_name){
      write.table(df2, i, row.names = F, sep='\t', col.names = T)
    }
  }
  One.Slice(df, x, base)
}

Auto.Slice(df = MS)