about data structure --- 'Set'

[wxy212]

Hello everyone,

If you look at the following tutorial, you will find the great advantage of using 'set' as a data structure.

http://docs.python.org/tut/node7.html#SECTION007400000000000000000

But it seems I need to import something before using it, otherwise it'll not be recognised. Could anybody please tell me what I should import?

Thanks in advance!

[bartonc]

Hello everyone,

If you look at the following tutorial, you will find the great advantage of using 'set' as a data structure.

http://docs.python.org/tut/node7.html#SECTION007400000000000000000

But it seems I need to import something before using it, otherwise it'll not be recognised. Could anybody please tell me what I should import?

Thanks in advance!

If your Python version is less than 2.4:[CODE=python]import Set as set
# or (I think)
from Future import Set as set[/CODE]Use the as modifier so that you code works with higher versions.

Otherwise, it's as simple as[CODE=python]
>>> set([1,1,3,4,5,5])
set([1, 3, 4, 5])
>>> [/CODE]Note that sets are not mutable (just like tuples). I've been using sets lately for their cool ability to subtract from one another:[CODE=python]
>>> set([1,2,3,4,5,6]) - set([4,5,6])
set([1, 2, 3])
>>> [/CODE]

[wxy212]

If your Python version is less than 2.4:[CODE=python]import Set as set
# or (I think)
from Future import Set as set[/CODE]Use the as modifier so that you code works with higher versions.

Otherwise, it's as simple as[CODE=python]
>>> set([1,1,3,4,5,5])
set([1, 3, 4, 5])
>>> [/CODE]Note that sets are not mutable (just like tuples). I've been using sets lately for their cool ability to subtract from one another:[CODE=python]
>>> set([1,2,3,4,5,6]) - set([4,5,6])
set([1, 2, 3])
>>> [/CODE]

cool! thanks a lot. the python version i used was 2.2.... that's why...