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Tupleware

Removing items from a tuple and rebuilding the tuple using the builtin zip function

You have a tuple like:
mytuple = [('harry',60,5),('susan',35,3),('guy',28,9),('peter',56,1)]
and want to turn it into:
newtuple = [('harry', 5), ('susan', 3), ('guy', 9), ('peter', 1)]

Solution: mytuple = [('harry',60,5),('susan',35,3),('guy',28,9),('peter',56,1)] names = [row[0] for row in mytuple] cats = [row[2] for row in mytuple] newtuple = zip(name,cats) Explanation: names = [row[0] for row in mytuple] is a short and smart way of doing the following: names = [] for row in mytuple: names.append(row[0]) This is perhaps easier to understand: every first row (remember programmers start counting by 0) in 'mytuple' is appended to the list 'names'. The concept of rows in tuples is clear when we change the notation of mytuple:

mytuple = [ # names, age, cats ('harry', 60, 5 ), ('susan', 35, 3), ('guy', 28, 9), ('peter', 56, 1) ] The same thing happens to 'cats' of course, and finally newtuple = zip(name,cats) uses zip which is a builtin function that returns a list of tuples where each tuple contains the i-th element from each of the argument sequences.

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