Create matrices laying out the data in rows, similar to
`matrix(..., byrow = TRUE)`

, with a nicer-to-read syntax.
This is useful for small matrices, e.g. covariance matrices, where readability
is important. The syntax is inspired by `tribble()`

.

frame_matrix(...)

## Arguments

... |
Arguments specifying the structure of a `frame_matrix` .
Column names should be formulas, and may only appear before the data. |

## Value

A matrix.

## Examples

frame_matrix(
~col1, ~col2,
1, 3,
5, 2
)

#> col1 col2
#> [1,] 1 3
#> [2,] 5 2