best way to transpose data.table

Question

[UPDATE: there is now a native transpose() function in data.table package]

I often need to transpose a data.table, every time

Answer 1

The current docs show a builtin transpose method.

Specifically, you can do:

transpose(mydata, keep.names = "col", make.names = "col0")
##     col row1 row2 row3
## 1: col1   11   21   31
## 2: col2   12   22   32
## 3: col3   13   23   33