how to add value to a tuple?

Question

I\'m working on a script where I have a list of tuples like (\'1\',\'2\',\'3\',\'4\'). e.g.:

list = [(\'1\',\'2\',\'3\',\'4\'),
        (\'2\',\         


        

Answer 1

Tuples are immutable and not supposed to be changed - that is what the list type is for. You could replace each tuple by originalTuple + (newElement,), thus creating a new tuple. For example:

t = (1,2,3)
t = t + (1,)
print t
(1,2,3,1)

But I'd rather suggest to go with lists from the beginning, because they are faster for inserting items.

And another hint: Do not overwrite the built-in name list in your program, rather call the variable l or some other name. If you overwrite the built-in name, you can't use it anymore in the current scope.

Answer 2

I was going through some details related to tuple and list, and what I understood is:

• Tuples are Heterogeneous collection data type
• Tuple has Fixed length (per tuple type)
• Tuple are Always finite

So for appending new item to a tuple, need to cast it to list, and do append() operation on it, then again cast it back to tuple.

But personally what I felt about the Question is, if Tuples are supposed to be finite, fixed length items and if we are using those data types in our application logics then there should not be a scenario to appending new items OR updating an item value in it. So instead of list of tuples it should be list of list itself, Am I right on this?

Answer 3

As mentioned in other answers, tuples are immutable once created, and a list might serve your purposes better.

That said, another option for creating a new tuple with extra items is to use the splat operator:

new_tuple = (*old_tuple, 'new', 'items')

I like this syntax because it looks like a new tuple, so it clearly communicates what you're trying to do.

Using splat, a potential solution is:

list = [(*i, ''.join(i)) for i in list]

Answer 4

Based on the syntax, I'm guessing this is Python. The point of a tuple is that it is immutable, so you need to replace each element with a new tuple:

list = [l + (''.join(l),) for l in list]
# output:
[('1', '2', '3', '4', '1234'), 
 ('2', '3', '4', '5', '2345'), 
 ('3', '4', '5', '6', '3456'), 
 ('4', '5', '6', '7', '4567')]

Answer 5

In Python, you can't. Tuples are immutable.

On the containing list, you could replace tuple ('1', '2', '3', '4') with a different ('1', '2', '3', '4', '1234') tuple though.

Answer 6

OUTPUTS = []
for number in range(len(list_of_tuples))):
    tup_ = list_of_tuples[number]
    list_ = list(tup_)  
    item_ = list_[0] + list_[1] + list_[2] + list_[3]
    list_.append(item_)
    OUTPUTS.append(tuple(list_))

OUTPUTS is what you desire