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Python

Posted by Nils Garland
Nils Garland
18,416 Points

Python range()

Could somebody explain what the range() function is doing here? I understand everything and I passed the challenge with this but I am not sure as to why I need to use range here? 

def combo(itr1,itr2):
  tuple_list= []
  for index in range(len(itr1)):
    tuple_list.append((itr1[index],itr2[index]))
  return tuple_list

Thanks!

1 Answer

Cody Te Awa
Cody Te Awa
8,820 Points

Hi Nils, The range function returns a range object that essentially is a type of iterable that can be used. For e.g.

x = list(range(5))
# x is [0, 1, 2, 3, 4]

range expects a number to decide how big the iterable will be and it also takes other params that can be seen if you type help(range). In your example:

for index in range(len(itr1)):
# len is evaluating the length of the list and returning it to the range function
# range is then receiving an integer that is the size of the list and creates an iterable
# that has the values starting from 0 up until the len of the list. e.g. [0, 1, 2, ...., len(itr1) -1]

If you have any further questions leave a comment! Hope this helps! Happy programming Nils! :) -CodyTheCoder