Creates a column index by interpreting each column name as a data column name
and a group name separated by sep. Only columns that are not row indices
are used. sep must occur exactly once in each column name.
sep_colgrp(x, sep, index_name = "group")
| x | A tibble |
|---|---|
| sep | A character delimiting the two parts of the name |
| index_name | A name for the new column index |
A grouped tibble