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Finding size of Variable

Mark Lawrence breamoreboy at yahoo.co.uk
Tue Feb 11 14:04:02 EST 2014 
On 11/02/2014 18:53, wxjmfauth at gmail.com wrote:
> Le lundi 10 février 2014 15:43:08 UTC+1, Tim Chase a écrit :
>> On 2014-02-10 06:07, wxjmfauth at gmail.com wrote:
>>
>>> Python does not save memory at all. A str (unicode string)
>>
>>> uses less memory only - and only - because and when one uses
>>
>>> explicitly characters which are consuming less memory.
>>
>>>
>>
>>> Not only the memory gain is zero, Python falls back to the
>>
>>> worse case.
>>
>>>
>>
>>>>>> sys.getsizeof('a' * 1000000)
>>
>>> 1000025
>>
>>>>>> sys.getsizeof('a' * 1000000 + 'oe')
>>
>>> 2000040
>>
>>>>>> sys.getsizeof('a' * 1000000 + 'oe' + '\U00010000')
>>
>>> 4000048
>>
>>
>>
>> If Python used UTF-32 for EVERYTHING, then all three of those cases
>>
>> would be 4000048, so it clearly disproves your claim that "python
>>
>> does not save memory at all".
>>
>>
>>
>>> The opposite of what the utf8/utf16 do!
>>
>>>
>>
>>>>>> sys.getsizeof(('a' * 1000000 + 'oe' +
>>
>>>>>> '\U00010000').encode('utf-8'))
>>
>>> 1000023
>>
>>>>>> sys.getsizeof(('a' * 1000000 + 'oe' +
>>
>>>>>> '\U00010000').encode('utf-16'))
>>
>>> 2000025
>>
>>
>>
>> However, as pointed out repeatedly, string-indexing in fixed-width
>>
>> encodings are O(1) while indexing into variable-width encodings (e.g.
>>
>> UTF8/UTF16) are O(N).  The FSR gives the benefits of O(1) indexing
>>
>> while saving space when a string doesn't need to use a full 32-bit
>>
>> width.
>>
>>
>
> A utf optimizes the memory and the performance at the same time.
> It behaves like a mathematical operator, a unique operator for
> a unique set of elements. Unbeatable.
>
> The FSR is an exclusive or mechanism. I you wish to
> same memory, you have to encode, and if you are encoding,
> maybe because you have to, one loses performance. Paradoxal.
>
> Your O(1) indexing works only and only because and
> when you are working explicitly with a "static" unicode
> string you never touch.
> It's a little bit the the "corresponding" performance
> case of the memory case.
>
> jmf
>

Why are you so rude as to continually post your nonsense here that not a 
single person believes, and at the same time still quite deliberately 
use gg to post it with double line spacing.  If you lack the courtesy to 
stop the former, please have the courtesy to stop the latter.

-- 
My fellow Pythonistas, ask not what our language can do for you, ask 
what you can do for our language.

Mark Lawrence

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