Question

Hi, I'm looking at the code for lecture 4, the last program, and am seeking a bit of clarification on the construct:
divisors = divisors + (i,)
Why does this create a list instead of a sum? Is it because of the () and ,? or does it change the type to str?
(full code below) Thanks!
# calculates all possible factors of x
x = 100
divisors = ()
for i in range(1, x):
if x%i == 0:#if there's no remainder
divisors = divisors + (i,)# create csv list of divisors used

print divisors
print divisors[0] + divisors[1]
print divisors[2:4]#prints divisors in range between positi

Answer 1

"divisors = ()" defines that it is a tuple. A tuple consists of a number of values separated by commas.

Answer 2

Cool, Thanks. That clears it up. So, when you add to a tuple, you just put another piece of data into the list of values.

Thanks again,

Kilgore

Answer 3

nope, when you add to tuple you create a new tuple that includes the old and new item(s).
```
>>>
>>> T = (1,2)
>>> id(T)
42281760
>>> T1 = T + (3,)
>>> id(T1)
42481184
>>> T
(1, 2)
>>> T1
(1, 2, 3)
>>> T2 = T1 + ()
>>> T1
(1, 2, 3)
>>> T2
(1, 2, 3)
>>> T1 == T2
True
>>> T1 is T2
False
>>> id(T1), id(T2)
(42481184, 42482624)
>>>
```

Answer 4

Cool, thanks for the demo. Between that, and some more reading, I should be well on my way (at least with this question).

Thanks again