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Python

Posted by Diego Murray
Diego Murray
2,515 Points

Trouble understanding BASIC PYTHON code

Please help me understand what this code is doing, exactly. In addition what is a counter and, in general, what usually goes in parenthesis when defining a function?

def add_list(list_of_numbers):
  counter = 0
  for item in list_of_numbers:
    counter + item
  return counter

1 Answer

Gunhoo Yoon
Gunhoo Yoon
5,027 Points 
def add_list(list_of_numbers): 
  counter = 0
  for item in list_of_numbers:
    counter + item
  return counter

I would probably change the name counter to result, total, sumup or something on that line because that seems more clear to me.

Here what above code will do.

  1. Takes a list, assuming all items in the list is number.

  2. Set the starting point to 0 in case of empty list. (counter variable)

  3. Go through each item in the list.

  4. Add each item to counter variable.

  5. After iterating through all item in the list return the counter which in this case sum of all items in list.

If something is unclear let me know what you don't understand.

Diego Murray
Diego Murray
2,515 Points

Gunhoo Yoon, so counter is an interchangeable name? Could you please elaborate a bit on step 2. What do you mean by starting point?

Gunhoo Yoon
Gunhoo Yoon
5,027 Points

counter is just a variable name that holds initially holds 0. Variable name can be anything as long as it doesn't collide with reserved words and follows naming convention.