Python 3 Tutorial - Sets
In this video tutorial you will learn what Python sets are and what they can do for you.
The demonstrations include intersection, union and difference set operations - both using member functions and with operators. Finally a brief example of how sets can positively affect the performance of your programs is shown.
The following source code was used in this video tutorial:
s1 = {1, 2, 9, 3, 1, 3, 7, 9, 3, 1, 3, 2}
s2 = {5, 8, 4, 3, 7, 8}
intersection = s1.intersection(s2)
s1 & s2 # binary and operator
union = s1.union(s2)
s1 | s2 # binary or operator
s1.difference(s2)
s1 - s2
example of how sets can help improve your program's performance
by removing a nested for loop (O(n*m))
query1 = list(range(1, 100000, 2)) # 1, 3, 5, ...
query2 = list(range(1, 100000, 3)) # 1, 4, 7, ...
nested loop
records = []
for record in query1:
if record in query2:
records.append(record)
and now with sets
queryset1 = set(query1)
queryset2 = set(query2)
records = list(queryset1.intersection(queryset2))
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This screencast was recorded using the kate editor, ipython3 shell and Kazam screencaster on Kubuntu 14.04.
On this page of the site you can watch the video online Python 3 Tutorial - Sets with a duration of hours minute second in good quality, which was uploaded by the user Gerald Senarclens de Grancy 10 July 2014, share the link with friends and acquaintances, this video has already been watched 3,432 times on youtube and it was liked by 40 viewers. Enjoy your viewing!
