What is not working with my "map" usage?

[Victor]

On Saturday, September 22, 2018 at 6:22:32 AM UTC-7, Peter Otten wrote:
> Victor via Python-list wrote:
> 
> > Let me use a different input args and display them below.  Basically, I am
> > hoping to add up all elements of each nested list.  So at first it should
> > start with [1,11,111] ==> 1+11+111 = 123.  But instead, it appears to take
> > the 1st element from each nested list to add up [1,2,3] = 6.   How should
> > it be corrected?  Thx.
> 
> I see three options. You can
> 
> (1) use a list comprehension
> 
> [add_all_elements(*sub) for sub in alist]
> 
> (2) replace map() with itertools.starmap()
> 
> list(itertools.starmap(add_all_elements, alist))
> 
> (3) change your function's signature from add_all_elements(*args) to 
> add_all_elements(args), either by modifying it directly or by wrapping it 
> into another function
> 
> list(map(lambda args: add_all_elements(*args), alist))
> 
> (3a) My personal preference would be to change the signature and then use 
> the list comprehension
> 
> def add_all_elements(args): ...
> [add_all_elements(sub) for sub in alist]

Hi Peter,
Thank you for your suggested solutions.  They all work.  But I just want to know what is wrong with my doing:

list(map(add_all_elements,*alist))

Theoretically, each list element is passed to add_all_elements.  And if my alist is [[1, 11, 111], [2, 22, 222], [3, 33, 333]], then the 1st list element  must be this [1,11,111] passed as args into add_all_elements.  

In other words, the following should have happened:  

>>> add_all_elements (*[1,11,111])
My args =  (1, 11, 111)

i = 1
BEFORE total = 0
AFTER total = 1

i = 11
BEFORE total = 1
AFTER total = 12

i = 111
BEFORE total = 12
AFTER total = 123

FINAL total = 123

123

Again, thanks!