insertion sort (snippet)

Python example 'insertion sort'. This is a demo of the insertion sorting algorithm in Python.

Functions in program:

• def sort_(arr,temporary=False,reverse=False):

insertion sort

Python beginners example: insertion sort

# -*- coding: utf-8 -*-

# Insertion Sort
# Ideal sorting algorithm for 
# small/small-medium data/array

# temporary parameter tells
# function to sort a copy of 
# orignal array, and not the array itself

# reverse parameter tells func
# to sort array in reverse/decending
# order


def sort_(arr,temporary=False,reverse=False):

    # Making copy of array if temporary is true
    if temporary:
        ar = arr[:]
    else:
        ar = arr

    # To blend every element
    # in correct position
    # length of total array is required
    length = len(ar)

    # After each iteration left-most
    # sub-array is completed sorted
    for i in range(1,length):
        # In each iteration we place
        # the current element to its
        # proper position in left sorted 
        # sub array
        tmp = ar[i]
        j = i-1
        if reverse:
            while j>=0 and tmp>ar[j]:
                ar[j+1]=ar[j]
                j-=1
            ar[j+1]=tmp
        else:
            while j>=0 and tmp<ar[j]:
                ar[j+1]=ar[j]
                j-=1
            ar[j+1]=tmp


    # if temporary, then returning
    # copied arr's sorted form
    # cuz if not returned, then function
    # is literally of no use
    if temporary:
        return ar


# See proper explaination 
# at: https://www.hotdogcode.com/insertion-sort/


# Testing
tests = [[7, 8, 9, 6, 4, 5, 3, 2, 1, 15], [1, 90, 1110, 1312, 1110, 98, 76, 54, 32, 10], ] # Add your test cases 

for test in tests:
    accend, decend = sort_(test, True), sort_(test, True, True)
    if accend == sorted(test) and decend == sorted(test, reverse = True):
        print("Orignal: {}".format(test))
        print("Sorted: {}".format(accend))
        print("Sorted(reverse): {}\n".format(decend))
    else:
        print("Something went wrong!\n")


# Seems our insertion sort works
# however for small/small-medium data/array!

Useful links

• Learn Python: https://pythonbasics.org
• Download Python: https://python.org