Question

I am teaching myself Python and am running into a strange problem. What I am trying to do is pass a list to a function, and have the function return a list where elements are the sum of the numbers around it, but what I thought would work produced some strange results, so I made a debug version of the code that still exhibts the behavior, which is as follows:

When I make an integer array, and pass it to an function which then uses a for loop print the individual values of the list, the numbers following the first one in each int are truncated.

For example, the following input and output:

Please enter a number: 101
Please enter a number: 202
Please enter a number: 303
Please enter a number: .
1
2
3

This happens no matter the input, if its 10, 101, or 13453 – the same behavior happens.

I know I am probably missing something simple, but for the sake of me, no amount of googling yields me a solution to this issue. Attached below is the code I am using to execute this. It is interesting to note: when printing the entire list outside of the for loop at any point, it returns the full and proper list (ie [‘101’, ‘202’, ‘303’])

Thanks!

temp = list()

def sum(list):
    print list
    for i in range(1, len(list)+1):
        print i
    return temp

L = list()
while True:
    input = raw_input("Please enter a number: ");
    if input.strip() == ".":
        break
    L.append(input);

print L

L2 = sum(L)
print L2

Answer 1

The loop

for i in range(1, len(my_list)+1):
    print i

iterates over the numbers from 1 to len(my_list), not over the items of the list. To do the latter, use

for x in my_list:
    print x

(I’ve renamed list to my_list to save you another headache.)