Beam¶

class abjad.spanners.Beam.Beam(*, beam_lone_notes=None, beam_rests=None, direction=None, durations=None, span_beam_count=1, stemlet_length=None)¶

Beam.

>>> staff = abjad.Staff("c'8 d'8 e'8 f'8 g'2")
>>> abjad.setting(staff).auto_beaming = False
>>> abjad.show(staff) 

>>> beam = abjad.Beam()
>>> abjad.attach(beam, staff[:2])
>>> beam = abjad.Beam()
>>> abjad.attach(beam, staff[2:4])
>>> abjad.show(staff) 

Tweaks beam positions:

>>> staff = abjad.Staff("c'8 d'8 e'8 f'8 g'2")
>>> abjad.setting(staff).auto_beaming = False
>>> beam = abjad.Beam()
>>> abjad.tweak(beam).positions = (3, 3)
>>> abjad.attach(beam, staff[:2])
>>> beam = abjad.Beam()
>>> abjad.tweak(beam).positions = (3, 3)
>>> abjad.attach(beam, staff[2:4])
>>> abjad.show(staff) 

Spanners can be tagged:

>>> staff = abjad.Staff("c'8 d'8 e'8 f'8 g'2")
>>> abjad.setting(staff).auto_beaming = False
>>> abjad.show(staff) 

>>> beam = abjad.Beam()
>>> abjad.attach(beam, staff[:2], tag='BEAM')
>>> beam = abjad.Beam()
>>> abjad.attach(beam, staff[2:4])
>>> abjad.show(staff) 

>>> abjad.f(staff)
\new Staff
\with
{
    autoBeaming = ##f
}
{
    c'8
    [ %! BEAM
    d'8
    ] %! BEAM
    e'8
    [
    f'8
    ]
    g'2
}

Attributes Summary

`beam_lone_notes`	Is true when beam should include lone notes.
`beam_rests`	Is true when beam should include rests.
`direction`	Gets direction.
`durations`	Gets durations.
`span_beam_count`	Gets span beam count.
`stemlet_length`	Gets stemlet length.

Special methods

(Spanner).__contains__(argument)¶

Is true when spanner contains argument.

Return type:	`bool`

(Spanner).__copy__(*arguments)¶

Copies spanner.

Does not copy spanner leaves.

(AbjadObject).__format__(format_specification='')¶

Formats Abjad object.

Set format_specification to '' or 'storage'. Interprets '' equal to 'storage'.

Returns string.

(Spanner).__getitem__(argument)¶

Gets leaf or selection identified by argument.

Return type:	`Union`[`Leaf`, `Selection`]

(Spanner).__iter__()¶

Iterates leaves in spanner.

Return type:	`Iterator`[+T_co]

(Spanner).__len__()¶

Gets number of leaves in spanner.

Return type:	`int`

(Spanner).__lt__(argument)¶

Is true when spanner is less than argument.

Trivial comparison to allow doctests to work.

Return type:	`bool`

(AbjadObject).__repr__()¶

Gets interpreter representation of Abjad object.

Returns string.

Read-only properties

beam_lone_notes¶

Is true when beam should include lone notes.

Todo

Teach durated beams to respect beam_lone_notes.

Does not beam lone notes:

>>> staff = abjad.Staff("c'8 d' e' f'")
>>> abjad.setting(staff).auto_beaming = False
>>> beam = abjad.Beam()
>>> abjad.attach(beam, staff[:1])
>>> abjad.show(staff) 

>>> staff = abjad.Staff("c'8 d'4 e'8 f'4 g'8")
>>> abjad.setting(staff).auto_beaming = False
>>> beam = abjad.Beam()
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

Does beam lone notes:

>>> staff = abjad.Staff("c'8 d' e' f'")
>>> abjad.setting(staff).auto_beaming = False
>>> beam = abjad.Beam(beam_lone_notes=True)
>>> abjad.attach(beam, staff[:1])
>>> abjad.show(staff) 

>>> staff = abjad.Staff("c'8 d'4 e'8 f'4 g'8")
>>> abjad.setting(staff).auto_beaming = False
>>> beam = abjad.Beam(beam_lone_notes=True)
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

Return type:	`Optional`[`bool`]

beam_rests¶

Is true when beam should include rests.

Without beamed rests:

>>> staff = abjad.Staff("c'8 d'8 r8 f'8 g'8 r4.")
>>> abjad.setting(staff).auto_beaming = False
>>> beam = abjad.Beam()
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

>>> abjad.f(staff)
\new Staff
\with
{
    autoBeaming = ##f
}
{
    c'8
    [
    d'8
    ]
    r8
    f'8
    [
    g'8
    ]
    r4.
}

Abjad beams no rests.

LilyPond beams no rests.

With beamed rests:

>>> staff = abjad.Staff("c'8 d'8 r8 f'8 g'8 r4.")
>>> abjad.setting(staff).auto_beaming = False
>>> beam = abjad.Beam(beam_rests=True)
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

>>> abjad.f(staff)
\new Staff
\with
{
    autoBeaming = ##f
}
{
    c'8
    [
    d'8
    r8
    f'8
    g'8
    r4.
    ]
}

Abjad beams all rests.

LilyPond beams only small-duration rests.

With beamed rests:

>>> staff = abjad.Staff("c'8 d'8 r4. f'8 g'8 r8")
>>> abjad.setting(staff).auto_beaming = False
>>> beam = abjad.Beam(beam_rests=True)
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

>>> abjad.f(staff)
\new Staff
\with
{
    autoBeaming = ##f
}
{
    c'8
    [
    d'8
    r4.
    f'8
    g'8
    r8
    ]
}

Abjad beams all rests.

LilyPond beams only small-duration rests.

With beamed skips:

>>> staff = abjad.Staff("c'8 d'8 s4. f'8 g'8 s8")
>>> abjad.setting(staff).auto_beaming = False
>>> beam = abjad.Beam(beam_rests=True)
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

>>> abjad.f(staff)
\new Staff
\with
{
    autoBeaming = ##f
}
{
    c'8
    [
    d'8
    s4.
    f'8
    g'8
    s8
    ]
}

Abjad beams all skips.

LilyPond beams all (internal) skips.

Return type:	`Optional`[`bool`]

direction¶

Gets direction.

Return type:	`Optional`[`String`]

durations¶

Gets durations.

Two groups:

>>> staff = abjad.Staff("c'16 d'16 e'16 f'16")
>>> durations = [(1, 8), (1, 8)]
>>> beam = abjad.Beam(durations=durations)
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

>>> beam.durations
(Duration(1, 8), Duration(1, 8))

Three groups:

>>> staff = abjad.Staff("c'16 d'16 e'8 f'16 c'16")
>>> abjad.setting(staff).auto_beaming = False
>>> durations = [(1, 8), (1, 8), (1, 8)]
>>> beam = abjad.Beam(
...     durations=durations,
...     span_beam_count=1,
...     )
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

Test ensures that leaf groups format correctly when they contain only one leaf.

Return type:	`Tuple`[`Duration`, …]

(Spanner).leaves¶

Gets leaves in spanner.

Return type:	`Selection`

span_beam_count¶

Gets span beam count.

Creates a single span beam between adjacent groups in spanner:

>>> staff = abjad.Staff("c'32 d'32 e'32 f'32")
>>> durations = [(1, 16), (1, 16)]
>>> beam = abjad.Beam(
...     durations=durations,
...     span_beam_count=1,
...     )
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

>>> beam.span_beam_count
1

Creates a double span beam between adjacent groups in spanner:

>>> staff = abjad.Staff("c'32 d'32 e'32 f'32")
>>> durations = [(1, 16), (1, 16)]
>>> beam = abjad.Beam(
...     durations=durations,
...     span_beam_count=2,
...     )
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

>>> beam.span_beam_count
2

Creates no span beam between adjacent groups in spanner:

>>> staff = abjad.Staff("c'32 d'32 e'32 f'32")
>>> durations = [(1, 16), (1, 16)]
>>> beam = abjad.Beam(
...     durations=durations,
...     span_beam_count=0,
...     )
>>> abjad.attach(beam, staff[:])
>>> abjad.show(staff) 

>>> beam.span_beam_count
0

Return type:	`int`

stemlet_length¶

Gets stemlet length.

>>> staff = abjad.Staff(
...     "r8 c' r c' g'2",
...     lilypond_type='RhythmicStaff',
...     )
>>> abjad.setting(staff).auto_beaming = False
>>> beam = abjad.Beam(beam_rests=True, stemlet_length=2)
>>> abjad.attach(beam, staff[:-1])
>>> abjad.show(staff) 

Return type:	`Union`[`int`, `float`, `None`]

(Spanner).tweaks¶

Gets tweaks.

Return type:	`Optional`[`LilyPondTweakManager`]