LilyPond program-reference: 3.1.68 NoteColumn

### 3.1.68 NoteColumn

NoteColumn objects are created by: Rhythmic_column_engraver.

Standard settings:

> `axes` (list):

>   `'(0 1)`

>   List of axis numbers. In the case of alignment grobs, this should contain only one number.

> `X-extent` (pair of numbers):

>   `ly:axis-group-interface::width`

>   Hard coded extent in X direction.

> `Y-extent` (pair of numbers):

>   `ly:axis-group-interface::height`

>   Hard coded extent in Y direction.

> `horizontal-skylines` (unknown):

>   `ly:separation-item::calc-skylines`

>   Two skylines, one to the left and one to the right of this grob.

This object supports the following interface(s): separation-item-interface, note-column-interface, item-interface, axis-group-interface and grob-interface.

#### Internals Reference