Python | Count the elements till first tuple
Sometimes, while working with records, we can have a problem in which an element of a record is another tuple records and we might have to count the element count that occur before the record. This is a problem which does not occur commonly, but having a solution to it is useful. Let’s discuss certain ways in which this task can be performed.
Method #1 : Using loop + isinstance() + enumerate()
This problem can be solved using the above functionalities. In this, we just loop through the elements using enumerate() to get the index count of it and check the type using isinstance().
Python3
# Python3 code to demonstrate working of # Elements till first tuple # using isinstance() + enumerate() + loop # initialize tuple test_tup = ( 1 , 5 , 7 , ( 4 , 6 ), 10 ) # printing original tuple print ("The original tuple : " + str (test_tup)) # Elements till first tuple # using isinstance() + enumerate() + loop for count, ele in enumerate (test_tup): if isinstance (ele, tuple ): break # printing result print ("Elements till the first tuple : " + str (count)) |
The original tuple : (1, 5, 7, (4, 6), 10) Elements till the first tuple : 3
Method #2 : Using takewhile() + sum() + isinstance() + lambda
The combination of above functions can also be used to solve this problem. In this, we use takewhile(), to iterate till a tuple and sum() to check the counter.
Python3
# Python3 code to demonstrate working of # Elements till first tuple # using takewhile() + sum() + isinstance() + lambda from itertools import takewhile # initialize tuple test_tup = ( 1 , 5 , 7 , ( 4 , 6 ), 10 ) # printing original tuple print ("The original tuple : " + str (test_tup)) # Elements till first tuple # using takewhile() + sum() + isinstance() + lambda res = sum ( 1 for sub in takewhile( lambda ele: not isinstance (ele, tuple ), test_tup)) # printing result print ("Elements till the first tuple : " + str (res)) |
The original tuple : (1, 5, 7, (4, 6), 10) Elements till the first tuple : 3