Question

This question is a followup to my previous question, Importing one long line of data into R.

I have a large data file consisting of a single line of text. The format resembles

Cat    14         15  Horse  16

I’d eventually like to get it into a data.frame. In the above example I would end up with two variables, two variables, Animal and Number. The number of characters in each “line” is fixed, so in the example above each line contains 11 characters, animals being the first 7 and numbers being the next four.

So what I’d like is a data frame that looks like:

Animal Number
   Cat     14
    NA     15
 Horse     16

Answer 1

You can read the file with read.fwf, specifying the column widths and the number of columns:

inp.fwf <- read.fwf("tmp.txt", widths = rep(c(7, 4), times = 3), as.is = TRUE)

Here the argument times = 3 works for your sample data; for your real file, you’ll have to indicate how many pairs there are and change times accordingly. If you don’t know how many entries you have, this might work:

inp.rl <- readLines("tmp.txt")
nchar(inp.rl)/11

This will give you a data.frame with one row and many columns. You need to break that into many rows and two columns:

inp.mat <- matrix(inp.fwf, byrow = TRUE, ncol = 2)

This will get you the correct shape for your data. The animal names are stored as character vectors, which you’ll probably want to change into factors, but at this point all the data is in R, so you can easily tweak it.