It is neither selection sort nor bubble sort, but an unnecessary bad sort. All of them, your sort, selection sort and bubble sort are of the same complexity, O(n^2).
Your sort sweeps over the array in two loops without consideration for if an element has reached its proper place (as in selection sort) or if an element has gained a place relative to the next (as in bubble sort). The extra code in bubble and selection sort make them far better than yours.
Compare, yourself:
def sort(arr):
print(arr)
n = len(arr)
for i in range(n):
for j in range(n):
if arr[i] < arr[j] :
arr[j], arr[i] = arr[i], arr[j]
print(arr)
def selectionsort(arr):
print(arr)
n = len(arr)
for i in range(n-1):
min_index = i
for j in range(i+1, n):
if arr[j] < arr[min_index]:
min_index = j
arr[i], arr[min_index] = arr[min_index], arr[i]
print(arr)
def bubblesort(arr):
print(arr)
n = len(arr)
for i in range(n):
for j in range(0, n-i-1):
if arr[j] > arr[j+1] :
arr[j], arr[j+1] = arr[j+1], arr[j]
print(arr)
print("sort:")
sort([4,6,3,2,7,1,8,5])
print("selectionsort:")
selectionsort([4,6,3,2,7,1,8,5])
print("bubblesort:")
bubblesort([4,6,3,2,7,1,8,5])
with the results:
sort:
[4, 6, 3, 2, 7, 1, 8, 5]
[6, 4, 3, 2, 7, 1, 8, 5]
[7, 4, 3, 2, 6, 1, 8, 5]
[8, 4, 3, 2, 6, 1, 7, 5]
[4, 8, 3, 2, 6, 1, 7, 5]
[3, 8, 4, 2, 6, 1, 7, 5]
[3, 4, 8, 2, 6, 1, 7, 5]
[2, 4, 8, 3, 6, 1, 7, 5]
[2, 3, 8, 4, 6, 1, 7, 5]
[2, 3, 4, 8, 6, 1, 7, 5]
[2, 3, 4, 6, 8, 1, 7, 5]
[1, 3, 4, 6, 8, 2, 7, 5]
[1, 2, 4, 6, 8, 3, 7, 5]
[1, 2, 3, 6, 8, 4, 7, 5]
[1, 2, 3, 4, 8, 6, 7, 5]
[1, 2, 3, 4, 6, 8, 7, 5]
[1, 2, 3, 4, 6, 7, 8, 5]
[1, 2, 3, 4, 5, 7, 8, 6]
[1, 2, 3, 4, 5, 6, 8, 7]
[1, 2, 3, 4, 5, 6, 7, 8]
selectionsort:
[4, 6, 3, 2, 7, 1, 8, 5]
[1, 6, 3, 2, 7, 4, 8, 5]
[1, 2, 3, 6, 7, 4, 8, 5]
[1, 2, 3, 6, 7, 4, 8, 5]
[1, 2, 3, 4, 7, 6, 8, 5]
[1, 2, 3, 4, 5, 6, 8, 7]
[1, 2, 3, 4, 5, 6, 8, 7]
[1, 2, 3, 4, 5, 6, 7, 8]
bubblesort:
[4, 6, 3, 2, 7, 1, 8, 5]
[4, 3, 6, 2, 7, 1, 8, 5]
[4, 3, 2, 6, 7, 1, 8, 5]
[4, 3, 2, 6, 1, 7, 8, 5]
[4, 3, 2, 6, 1, 7, 5, 8]
[3, 4, 2, 6, 1, 7, 5, 8]
[3, 2, 4, 6, 1, 7, 5, 8]
[3, 2, 4, 1, 6, 7, 5, 8]
[3, 2, 4, 1, 6, 5, 7, 8]
[2, 3, 4, 1, 6, 5, 7, 8]
[2, 3, 1, 4, 6, 5, 7, 8]
[2, 3, 1, 4, 5, 6, 7, 8]
[2, 1, 3, 4, 5, 6, 7, 8]
[1, 2, 3, 4, 5, 6, 7, 8]
It doesn't make a big difference on small arrays but on large arrays it make a lot of difference (but then there are other methods).