How to convert a csv list to a character vector in R

Question

I am new to R. I have a .csv file with a series of identifiers in a column that look like:

F653
F763
F121
F123
...

These values are in a vertical column, and I want to import them into R in the format

data <- c("F653", "F763", "F121", "F123")

I'm sure this is relatively easy but I'm stuck, so any advice would help.

Answer 1

Given a file that only has one column file_1.csv, e.g.:

F653
F763
F121
F123

... it isn't really a CSV file because there are no commas separating the values. Nevertheless, you can read it with dat1 <- read.csv("file_1.csv",header=F) to obtain:

> dat1
    V1
1 F653
2 F763
3 F121
4 F123

Alternatively, a two-column comma-separated file file.csv:

F653,1
F763,2
F121,3
F123,4

... the file can be read in like:

> dat <- read.csv("file.csv",header=F)
> dat
    V1 V2
1 F653  1
2 F763  2
3 F121  3
4 F123  4

However, dat and dat1 are both data tables. If you want a vector instead of a data table from file_1.csv, you can get that like this:

> dat <- read.csv("file.csv",header=F)$V1
> dat
[1] F653 F763 F121 F123
Levels: F121 F123 F653 F763

You can see that the vector has been read as a factor by default.

If you want a character vector, you can get that from:

> as.character(dat)
[1] "F653" "F763" "F121" "F123"

Answer 2

I'd like to add another solution. It provides a character vector right away.

dat = readLines("file.csv")