Python & Music: Performance question

[Nicodemus]

David Asorey Álvarez wrote:

>Hello, group.
>
>I'm developing a small music program, and I have some doubts.
>
>   I want define a class, Note, which represents a note. It has two
>attributes, pitch and duration (quarter note, half note, etc). There
>will be a lot of instances of this object, maybe hundreds of notes,
>and the program needs access to all of this objects and read its
>attributes.
>   Which implementation will be more efficient?
>
>Implementation A:
>
>class Note:
>   def __init__(self, pitch, duration):
>      self.pitch = pitch
>      self.duration = duration
>   def change_pitch(factor): pass
>   def change_duration(factor): pass
>   # more methods ...
>  
>
Try using __slots__... this will save memory.

class Note(object):
    __slots__ = ['pitch',  'duration' ]
    def __init__(self, pitch, duration):
        self.pitch = pitch
        self.duration = duration
    # more methods

>Implementation B:
>
>class Note:
>   def __init__(self, pitch, duration):
>      self["pitch"] = pitch
>      self["duration"] = duration
>   def change_pitch(factor): pass
>   def change_duration(factor): pass
>   # more methods ...
>  
>
This won't even work, unless you define a __setitem__ method. And if 
you're looking for efficiency, that's not the way to go.

Hope that helps,
Nicodemus.