🔒 is this code pythonic?

[fierce summit]

def merge_sort(a_list):
 if len(a_list) > 1:
  mid = len(a_list) // 2
  left_half = a_list[:mid]
  right_half = a_list[mid:]
  merge_sort(left_half)
  merge_sort(right_half)
  left_index = 0
  right_index = 0
  alist_index = 0
  
  if left_index < len(left_half) and right_ind < len(right_half):
   if left_half[left_index] <= right_half[right_index]:
    a_list[alist_index] = left_half[left_index]
    left_index += 1
   else:
    a_list[alist_index] = right_half[right_index]
    right_index += 1
   alist_index += 1
  
  if left_index < len(left_half):
   a_list[alist_index] = left_half[left_index]
   left_index += 1
   alist_index += 1
  
  if right_index < len(right_half):
   a_list[alist_index] = right_half[right_index]
   right_index += 1
   alist_index += 1
  
  return a_list

[flat dagger]

@fierce summit

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[pseudo pelican]

!e

def merge_sort(a_list):
 if len(a_list) > 1:
  mid = len(a_list) // 2
  left_half = a_list[:mid]
  right_half = a_list[mid:]
  merge_sort(left_half)
  merge_sort(right_half)
  left_index = 0
  right_index = 0
  alist_index = 0
  
  if left_index < len(left_half) and right_index < len(right_half):
   if left_half[left_index] <= right_half[right_index]:
    a_list[alist_index] = left_half[left_index]
    left_index += 1
   else:
    a_list[alist_index] = right_half[right_index]
    right_index += 1
   alist_index += 1
  
  if left_index < len(left_half):
   a_list[alist_index] = left_half[left_index]
   left_index += 1
   alist_index += 1
  
  if right_index < len(right_half):
   a_list[alist_index] = right_half[right_index]
   right_index += 1
   alist_index += 1
  
  return a_list
print(merge_sort([7, 2, 3, 7, 9, 10, 3, 2, 6, 5]))

[flat dagger]

:white_check_mark: Your 3.12 eval job has completed with return code 0.

[2, 7, 2, 7, 9, 10, 3, 2, 6, 5]

[pseudo pelican]

that's my point
the code after the recursive calls don't properly merge the sorted lists

[fierce summit]

wait it worked yesterday, i think i made an error i will fix it

1 sec

[pseudo pelican]

did you test it on a smaller list? because merging the two lists should require some form of iteration, but you only have two sets of if statements

which might work if the list was like only 4 elements

[fierce summit]

im an idiot

i wrote an if statement instead of running a while loop

'''py

def merge_sort(a_list):
 if len(a_list) > 1:
  mid = len(a_list) // 2
  left_half = a_list[:mid]
  right_half = a_list[mid:]
  merge_sort(left_half)
  merge_sort(right_half)
  left_index = 0
  right_index = 0
  alist_index = 0
  
  while left_index < len(left_half) and right_ind < len(right_half):
   if left_half[left_index] <= right_half[right_index]:
    a_list[alist_index] = left_half[left_index]
    left_index += 1
   else:
    a_list[alist_index] = right_half[right_index]
    right_index += 1
   alist_index += 1
  
  while left_index < len(left_half):
   a_list[alist_index] = left_half[left_index]
   left_index += 1
   alist_index += 1
  
  while right_index < len(right_half):
   a_list[alist_index] = right_half[right_index]
   right_index += 1
   alist_index += 1
  
  return a_list

this

this works

[pseudo pelican]

!e

def merge_sort(a_list):
 if len(a_list) > 1:
  mid = len(a_list) // 2
  left_half = a_list[:mid]
  right_half = a_list[mid:]
  merge_sort(left_half)
  merge_sort(right_half)
  left_index = 0
  right_index = 0
  alist_index = 0
  
  while left_index < len(left_half) and right_index < len(right_half):
   if left_half[left_index] <= right_half[right_index]:
    a_list[alist_index] = left_half[left_index]
    left_index += 1
   else:
    a_list[alist_index] = right_half[right_index]
    right_index += 1
   alist_index += 1
  
  while left_index < len(left_half):
   a_list[alist_index] = left_half[left_index]
   left_index += 1
   alist_index += 1
  
  while right_index < len(right_half):
   a_list[alist_index] = right_half[right_index]
   right_index += 1
   alist_index += 1
  
  return a_list
print(merge_sort([7, 2, 3, 7, 9, 10, 3, 2, 6, 5]))

[flat dagger]

:white_check_mark: Your 3.12 eval job has completed with return code 0.

[2, 2, 3, 3, 5, 6, 7, 7, 9, 10]

[pseudo pelican]

right

now onto making it pythonic

a few things
the if statement at the top could be inverted into a guard clause, which reduces nesting

if len(a_list) <= 1:
    return a_list
(...rest of code...)

[pseudo pelican]

I would probably extract the logic of merging the two sorted lists into its own method

otherwise the code looks ok

[fierce summit]

the sort method is more effecient, i'll just use that

my code was useless

[fierce summit]

by the way how did you run the code in discord

im noob

[pseudo pelican]

!e

code here

[fierce summit]

!e

[flat dagger]

Missing required argument

code

[fierce summit]

!e print("Thanks")

[flat dagger]

:white_check_mark: Your 3.13 free threaded eval job has completed with return code 0.

Thanks

[flat dagger]

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