### 5.4.2 Direction and placement

In typesetting music the direction and placement of many items is a matter of choice. For example, the stems of notes can be directed up or down; lyrics, dynamics, and other expressive marks may be placed above or below the staff; text may be aligned left, right or center; etc. Most of these choices may be left to be determined automatically by LilyPond, but in some cases it may be desirable to force a particular direction or placement.

#### Articulation direction indicators

By default some directions are always up or always down (e.g. dynamics or fermata), while other things can alternate between up or down based on the stem direction (like slurs or accents).

The default action may be overridden by prefixing the articulation by a direction indicator. Three direction indicators are available: `^` (meaning “up”), `_` (meaning “down”) and `-` (meaning “use default direction”). The direction indicator can usually be omitted, in which case `-` is assumed, but a direction indicator is always required before

- `\tweak` commands
- `\markup` commands
- `\tag` commands
- string markups, e.g. -"string"
- fingering instructions, e.g. `-1`
- articulation shortcuts, e.g. `-.`, `->`, `--`

Direction indicators affect only the next note:

>     c2( c)
>     c2_( c)
>     c2( c)
>     c2^( c)

#### The direction property

The position or direction of many layout objects is controlled by the `direction` property.

The value of the `direction` property may be set to `1`, meaning “up” or “above”, or to `-1`, meaning “down” or “below”. The symbols `UP` and `DOWN` may be used instead of `1` and `-1` respectively. The default direction may be specified by setting `direction` to `0` or `CENTER`. Alternatively, in many cases predefined commands exist to specify the direction. These are of the form

>     \xxxUp, \xxxDown or \xxxNeutral

where `\xxxNeutral` means “use the default” direction. See Within-staff objects.

In a few cases, arpeggio for example, the value of the `direction` property can specify whether the object is to be placed to the right or left of the parent. In this case `-1` or `LEFT` means “to the left” and `1` or `RIGHT` means “to the right”. `0` or `CENTER` means “use the default” direction.

These indications affect all notes until they are canceled.

>     c2( c)
>     \slurDown
>     c2( c)
>     c2( c)
>     \slurNeutral
>     c2( c)

In polyphonic music, it is generally better to specify an explicit `voice` than change an object’s direction. For more information. See Multiple voices.

#### See also

Learning Manual: Within-staff objects.

Notation Reference: Multiple voices.

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#### LilyPond — Notation Reference v2.18.2 (稳定分支).