from collections.abc import Iterable
from typing import Union
import abjad
from .. import select
[docs]def rhythms_are_identical(selections: Union[Iterable[abjad.Component],
Iterable[abjad.Selection],
],
) -> bool:
r"""Returns a :obj:`bool` representing whether two or more selections are
rhytmically identical or not. Input argument must be an iterable made of
two or more |abjad.Selection|'s.
Basic usage:
When the pitches and effective durations of all leaves in all
selections are identical, this function returns ``True``:
>>> container1 = abjad.Staff(r"c'4 d'4 e'4 f'4")
>>> container2 = abjad.Staff(r"c''4 b'4 a'4 g'4")
>>> selections = [container1[:], container2[:]]
>>> auxjad.get.rhythms_are_identical(selections)
True
Rests and chords are also handled.
>>> container1 = abjad.Staff(r"c'4. d'8 e'4 f'4 <g' a'>2 r2")
>>> container2 = abjad.Staff(r"c''4. r8 <b' a'>4 r4 g'2 f'2")
When comparing rests, this function considers consecutive rests as a
single logical tie.
>>> container1 = abjad.Staff(
... r"c'4 ~ c'16 r8. r8. <d' e'>16 ~ <d' e'>4"
... )
>>> container2 = abjad.Staff(r"r4 r16 c''8. ~ c''8. b'16 ~ b'4")
>>> selections = [container1[:], container2[:]]
>>> auxjad.get.rhythms_are_identical(selections)
True
>>> container1 = abjad.Staff(
... r"c'4 ~ c'16 r8. r8. <d' e'>16 ~ <d' e'>4"
... )
>>> container2 = abjad.Staff(r"r4 r16 c''8. b'8. a'16 ~ a'4")
>>> selections = [container1[:], container2[:]]
>>> auxjad.get.rhythms_are_identical(selections)
False
This function can handle multiple selections, and will compare them
among each other returning ``True`` if all are identical:
>>> container1 = abjad.Staff(r"c'4 d'4 e'4 f'4 <g' a'>2 r2")
>>> container2 = abjad.Staff(r"c''4 r4 <b' a'>4 r4 g'2 f'2")
>>> container3 = abjad.Staff(r"c'''4 c'''4 b''4 b''4 a''2 a''2")
>>> container4 = abjad.Staff(r"c4 d4 e4 f4 g2 a2")
>>> selections = [
... container1[:],
... container2[:],
... container3[:],
... container4[:],
... ]
>>> auxjad.get.rhythms_are_identical(selections)
True
.. note::
Auxjad automatically adds this function as an extension function to
|abjad.get|. It can thus be used from either |auxjad.get|_ or
|abjad.get| namespaces. Therefore, the two lines below are equivalent:
>>> container1 = abjad.Staff(r"c'4 d'4 e'4 f'4")
>>> container2 = abjad.Staff(r"c''4 b'4 a'4 g'4")
>>> selections = [container1[:], container2[:]]
>>> auxjad.get.rhythms_are_identical(selections)
True
>>> abjad.get.rhythms_are_identical(selections)
True
Effective durations:
Even if all leaves of both selections are identical in relation to both
pitches and written durations, the function considers the effective
durations. This means that situations like the one below do not yield a
false positive:
>>> container1 = abjad.Staff(r"c'4 d'4 e'4 f'4 <g' a'>2 r2")
>>> container2 = abjad.Staff(
... r"\times 3/2 {c'4 d'4 e'4} f'4 <g' a'>2 r2"
... )
>>> selections = [container1[:], container2[:]]
>>> auxjad.get.rhythms_are_identical(selections)
False
Grace notes:
This function also handles grace notes.
>>> container1 = abjad.Staff(r"c'4 d'4 e'4 f'4")
>>> container2 = abjad.Staff(r"c'4 \grace{d'4} d'4 e'4 f'4")
>>> selection1 = abjad.select(container1)
>>> selection2 = abjad.select(container2)
>>> selections = [selection1, selection2]
>>> auxjad.get.rhythms_are_identical(selections)
False
>>> container1 = abjad.Staff(r"c'4 d'4 e'4 f'4 <g' a'>2 r2")
>>> container2 = abjad.Staff(
... r"c'4 \grace{c''4} d'4 e'4 f'4 <g' a'>2 r2"
... )
>>> selection1 = abjad.select(container1)
>>> selection2 = abjad.select(container2)
>>> selections = [selection1, selection2]
>>> auxjad.get.rhythms_are_identical(selections)
False
>>> container1 = abjad.Staff(
... r"c'4 \grace{c''4} d'4 e'4 f'4 <g' a'>2 r2"
... )
>>> container2 = abjad.Staff(
... r"c'4 \grace{b4} d'4 e'4 f'4 <g' a'>2 r2"
... )
>>> selection1 = abjad.select(container1)
>>> selection2 = abjad.select(container2)
>>> selections = [selection1, selection2]
>>> auxjad.get.rhythms_are_identical(selections)
True
.. warning::
It is important to create selections using |abjad.select()| as shown in
the example above, instead of using the syntax ``container[:]``, since
the latter ignores grace notes.
.. note::
It is important to note it is the contents of the containers which are
compared, so containers of different classes can still return a
``True`` value.
>>> container1 = abjad.Container(r"c'4 d'4 e'4 f'4")
>>> container2 = abjad.Staff(r"c'4 d'4 e'4 f'4")
>>> selections = [container1[:], container2[:]]
>>> auxjad.get.rhythms_are_identical(selections)
True
"""
if not isinstance(selections, Iterable):
raise TypeError("argument must be an iterable of 'abjad.Selection's "
"or 'abjad.Component's")
for selection in selections:
if not isinstance(selection, (abjad.Component, abjad.Selection)):
raise TypeError("argument must be an iterable of "
"'abjad.Selection's or 'abjad.Component's")
for index, selection1 in enumerate(selections[:-1]):
for selection2 in selections[index + 1:]:
logical_selections1 = [logical_selection for logical_selection
in select.logical_selections(selection1)]
logical_selections2 = [logical_selection for logical_selection
in select.logical_selections(selection2)]
if len(logical_selections1) != len(logical_selections2):
return False
for logical_sel1, logical_sel2 in zip(logical_selections1,
logical_selections2,
):
if (abjad.get.duration(logical_sel1)
!= abjad.get.duration(logical_sel2)):
return False
leaf1 = logical_sel1.leaf(0)
leaf2 = logical_sel2.leaf(0)
leaf1_graces = abjad.get.before_grace_container(leaf1)
leaf2_graces = abjad.get.before_grace_container(leaf2)
if not isinstance(leaf1_graces, type(leaf2_graces)):
return False
return True