Inversion¶
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class
abjad.pitch.Inversion.
Inversion
(*, axis=None)¶ Inversion operator.
>>> abjad.Inversion() Inversion()
>>> abjad.Inversion(axis=15) Inversion(axis=NamedPitch("ef''"))
Object model of twelve-tone inversion operator.
Attributes Summary
__add__
Composes inversion and operator. __call__
Calls inversion on argument. __radd__
Right-addition not defined on inversion. __str__
Gets string representation of operator. axis
Gets axis of inversion. Special methods
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__add__
(operator)¶ Composes inversion and operator.
Example segment:
>>> items = [0, 2, 4, 5] >>> segment = abjad.PitchClassSegment(items=items) >>> abjad.show(segment)
Example operators:
>>> inversion = abjad.Inversion() >>> transposition = abjad.Transposition(n=3)
Transposition followed by inversion:
>>> operator = inversion + transposition >>> str(operator) 'IT3'
>>> segment_ = operator(segment) >>> abjad.show(segment_)
Inversion followed by transposition:
>>> operator = transposition + inversion >>> str(operator) 'T3I'
>>> segment_ = operator(segment) >>> abjad.show(segment_)
Returns compound operator:
>>> abjad.f(operator) abjad.CompoundOperator( operators=[ abjad.Inversion(), abjad.Transposition( n=3, ), ], )
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__call__
(argument)¶ Calls inversion on argument.
Inverts numbered pitch-class:
>>> inversion = abjad.Inversion() >>> pitch_class = abjad.NumberedPitchClass(1) >>> inversion(pitch_class) NumberedPitchClass(11)
Inverts numbered pitch:
>>> inversion = abjad.Inversion() >>> pitch = abjad.NumberedPitch(15) >>> inversion(pitch) NumberedPitch(-15)
Inverts named pitch:
>>> inversion = abjad.Inversion() >>> pitch = abjad.NamedPitch("d'") >>> inversion(pitch) NamedPitch('bf')
Inverts named pitch class:
>>> inversion = abjad.Inversion() >>> pitch_class = abjad.NamedPitchClass('d') >>> inversion(pitch_class) NamedPitchClass('bf')
Inverts pitch segment:
>>> inversion = abjad.Inversion() >>> segment = abjad.PitchSegment("c' d' e'") >>> inversion(segment) PitchSegment("c' bf af")
Inverts pitch class segment:
>>> inversion = abjad.Inversion() >>> segment = abjad.PitchClassSegment("c d e") >>> inversion(segment) PitchClassSegment("c bf af")
Inverts pitch class set:
>>> inversion = abjad.Inversion() >>> setting = abjad.PitchClassSet("c d e") >>> inversion(setting) PitchClassSet(['c', 'af', 'bf'])
Returns new object with type equal to that of argument.
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(
AbjadValueObject
).__copy__
(*arguments)¶ Copies Abjad value object.
Returns new Abjad value object.
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(
AbjadValueObject
).__eq__
(argument)¶ Is true when all initialization values of Abjad value object equal the initialization values of
argument
.Returns true or false.
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(
AbjadObject
).__format__
(format_specification='')¶ Formats Abjad object.
Set
format_specification
to''
or'storage'
. Interprets''
equal to'storage'
.Returns string.
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(
AbjadValueObject
).__hash__
()¶ Hashes Abjad value object.
Returns integer.
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__radd__
(operator)¶ Right-addition not defined on inversion.
>>> abjad.Inversion().__radd__(abjad.Inversion()) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/Users/josiah/Source/github.com/Abjad/abjad/abjad/pitch/Inversion.py", line 215, in __radd__ raise NotImplementedError(message) NotImplementedError: right-addition not defined on Inversion.
Raises not implemented error.
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(
AbjadObject
).__repr__
()¶ Gets interpreter representation of Abjad object.
Returns string.
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__str__
()¶ Gets string representation of operator.
>>> str(abjad.Inversion()) 'I'
>>> str(abjad.Inversion(axis=15)) 'I(Eb5)'
Read-only properties
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axis
¶ Gets axis of inversion.
>>> inversion = abjad.Inversion() >>> inversion.axis is None True
>>> inversion = abjad.Inversion(axis=15) >>> inversion.axis NamedPitch("ef''")
Returns named pitch or none.
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