Takes an existing column and uses it as rownames instead. This is useful
when turning a data.frame into a matrix.
Inspired by the tibble package's column_to_row which is now
deprecated if done on a tibble object. By coercing to a
data.frame this problem is avoided.
Usage
column_to_rownames(x, loc = 1)
Value
Returns a data.frame with the specified column
moved to rownames.