> library(data.table)
> fwrite(iris, tmp <- tempfile())
> fread(file = tmp, select = c(5, 1, 3), skip = 0)
Petal.Length Species Sepal.Length
1: 1.4 setosa 5.1
2: 1.4 setosa 4.9
3: 1.3 setosa 4.7
4: 1.5 setosa 4.6
5: 1.4 setosa 5.0
---
146: 5.2 virginica 6.7
147: 5.0 virginica 6.3
148: 5.2 virginica 6.5
149: 5.4 virginica 6.2
150: 5.1 virginica 5.9
> fread(file = tmp, select = c(5, 1, 3), skip = 1)
V3 V5 V1
1: 1.4 setosa 5.1
2: 1.4 setosa 4.9
3: 1.3 setosa 4.7
4: 1.5 setosa 4.6
5: 1.4 setosa 5.0
---
146: 5.2 virginica 6.7
147: 5.0 virginica 6.3
148: 5.2 virginica 6.5
149: 5.4 virginica 6.2
150: 5.1 virginica 5.9
When selecting
c(5, 1, 3)from a file containingiris, I expected to haveSpeciesfirst.