def select(items=None):
r"""
Selects ``items`` or makes select expression.
.. container:: example
Selects first two notes in staff:
>>> staff = abjad.Staff("c'4 d' e' f'")
>>> selection = abjad.select(staff[:2]).leaves(pitched=True)
>>> for note in selection:
... abjad.override(note).note_head.color = 'red'
>>> abjad.show(staff) # doctest: +SKIP
.. docs::
>>> abjad.f(staff)
\new Staff
{
\once \override NoteHead.color = #red
c'4
\once \override NoteHead.color = #red
d'4
e'4
f'4
}
.. container:: example
Returns selection agent:
>>> abjad.select(staff)
Selection([Staff("c'4 d'4 e'4 f'4")])
>>> abjad.select()
abjad.select()
"""
import abjad
if items is None:
return abjad.Expression().select()
return abjad.Selection(items=items)
def iterate(client=None):
r"""
Makes iteration agent.
.. container:: example
Iterates leaves:
>>> staff = abjad.Staff("c'4 e'4 d'4 f'4")
>>> abjad.show(staff) # doctest: +SKIP
.. docs::
>>> abjad.f(staff)
\new Staff
{
c'4
e'4
d'4
f'4
}
>>> for leaf in abjad.iterate(staff).leaves():
... leaf
...
Note("c'4")
Note("e'4")
Note("d'4")
Note("f'4")
"""
import abjad
if client is not None:
return abjad.Iteration(client=client)
expression = abjad.Expression()
expression = expression.iterate()
return expression
def sequence(items=None, **keywords):
r'''Makes sequence or sequence expression.
.. container:: example
.. container:: example
Makes sequence:
>>> abjad.sequence([1, 2, [3, [4]], 5])
Sequence([1, 2, [3, [4]], 5])
.. container:: example expression
Makes sequence expression:
>>> expression = abjad.sequence()
>>> expression([1, 2, [3, [4]], 5])
Sequence([1, 2, [3, [4]], 5])
.. container:: example
Flattens, reverses and slices sequence:
.. container:: example
>>> sequence_ = abjad.sequence([1, 2, [3, [4]], 5])
>>> sequence_
Sequence([1, 2, [3, [4]], 5])
>>> sequence_ = sequence_.flatten(depth=-1)
>>> sequence_
Sequence([1, 2, 3, 4, 5])
>>> sequence_ = sequence_.reverse()
>>> sequence_
Sequence([5, 4, 3, 2, 1])
>>> sequence_ = sequence_[-3:]
>>> sequence_
Sequence([3, 2, 1])
.. container:: example expression
>>> expression = abjad.sequence()
>>> expression = expression.flatten(depth=-1)
>>> expression = expression.reverse()
>>> expression = expression[-3:]
>>> expression([1, 2, [3, [4]], 5])
Sequence([3, 2, 1])
Returns sequence when `items` is not none.
Returns sequence expression when `items` is none.
'''
import abjad
if items is not None:
return abjad.Sequence(items=items, **keywords)
else:
expression = abjad.Expression()
expression = expression.sequence(**keywords)
return expression
def label(client=None, deactivate=None, tag=None):
r"""
Makes label agent or label expression.
.. container:: example
Labels logical ties with start offsets:
>>> staff = abjad.Staff(r"\times 2/3 { c'4 d'4 e'4 ~ } e'4 ef'4")
>>> abjad.label(staff).with_start_offsets(direction=abjad.Up)
Duration(1, 1)
>>> abjad.override(staff).text_script.staff_padding = 4
>>> abjad.override(staff).tuplet_bracket.staff_padding = 0
>>> abjad.show(staff) # doctest: +SKIP
.. docs::
>>> abjad.f(staff)
\new Staff
\with
{
\override TextScript.staff-padding = #4
\override TupletBracket.staff-padding = #0
}
{
\times 2/3 {
c'4
^ \markup { 0 }
d'4
^ \markup { 1/6 }
e'4
^ \markup { 1/3 }
~
}
e'4
ef'4
^ \markup { 3/4 }
}
See the ``Label`` API entry for many more examples.
.. container:: example expression
Initializes positionally:
>>> expression = abjad.label()
>>> expression(staff)
Label(client=<Staff{3}>)
Initializes from keyword:
>>> expression = abjad.label()
>>> expression(client=staff)
Label(client=<Staff{3}>)
Makes label expression:
>>> expression = abjad.label()
>>> expression = expression.with_start_offsets()
>>> staff = abjad.Staff(r"\times 2/3 { c'4 d'4 e'4 ~ } e'4 ef'4")
>>> expression(staff)
Duration(1, 1)
>>> abjad.override(staff).text_script.staff_padding = 4
>>> abjad.override(staff).tuplet_bracket.staff_padding = 0
>>> abjad.show(staff) # doctest: +SKIP
.. docs::
>>> abjad.f(staff)
\new Staff
\with
{
\override TextScript.staff-padding = #4
\override TupletBracket.staff-padding = #0
}
{
\times 2/3 {
c'4
^ \markup { 0 }
d'4
^ \markup { 1/6 }
e'4
^ \markup { 1/3 }
~
}
e'4
ef'4
^ \markup { 3/4 }
}
See the ``Label`` API entry for many more examples.
Returns label agent when ``client`` is not none.
Returns label expression when ``client`` is none.
"""
import abjad
if client is not None:
return abjad.Label(
client=client,
deactivate=deactivate,
tag=tag,
)
expression = abjad.Expression()
expression = expression.label(tag=tag)
return expression