Bubble sort in python

Bubble sort python code.

def bubble_sort(A):
    n = len(A)    
    for i in range(0,n):
        for j in range (i+1,n):
            if A[i]>A[j]:
                A[i],A[j]=A[j], A[i]

if __name__=="__main__":
    A = [7,3,5,2]
    print A
    bubble_sort(A)
    print A

Output:

[7, 3, 5, 2]
[2, 3, 5, 7]

Selection sort in python

Selection sort python code.

def get_index_of_smallest(A, i):
    index_of_smallest = i
    for j in range(i+1, len(A)):
        if A[index_of_smallest]>A[j]:
            index_of_smallest = j;
    return index_of_smallest


def selection_sort(A):
    for i in range (0, len(A)):
        index_of_smallest = get_index_of_smallest(A,i)
        A[index_of_smallest], A[i] = A[i], A[index_of_smallest]

if __name__=="__main__":
    A = [7,3,5,2]
    print A
    selection_sort(A)
    print A

Output:

[7, 3, 5, 2]
[2, 3, 5, 7]

Insertion sort in python

Insertion sort python code.

def insert(A,i):
    value = A[i]
    j = i
    while j != 0 and A[j-1]>value:
        A[j] = A[j-1]
        j = j - 1
    A[j] = value


def insertion_sort(A):
     for i in range(len(A)):
         insert(A, i)

if __name__=="__main__":
    A = [7,3,5,2]
    print A
    insertion_sort(A)
    print A

Output:

[7, 3, 5, 2]
[2, 3, 5, 7]

python sort dictionary

Using sorted we can also dictionary data.

d={}
(d['a'],d['o'],d['g'])=("alpha","omega","gamma")

print d
for k in sorted( d.keys() ): 
   print k," ",d[k]

print d

Output:

{'a': 'alpha', 'g': 'gamma', 'o': 'omega'}
a   alpha
g   gamma
o   omega
{'a': 'alpha', 'g': 'gamma', 'o': 'omega'}

python sort tuple

Some example for sort tuple are given

a=[(1,"b"),(2,"a"),(1,"e")]
print a
print sorted(a)

def myTSort(d):
    return d[0] # sort according to first value

print sorted(a,key=myTSort)
print sorted(a,key=myTSort, reverse=True)
print a

Output:

[(1, 'b'), (2, 'a'), (1, 'e')]
[(1, 'b'), (1, 'e'), (2, 'a')]
[(1, 'b'), (1, 'e'), (2, 'a')]
[(2, 'a'), (1, 'b'), (1, 'e')]
[(1, 'b'), (2, 'a'), (1, 'e')]

python string array sort: pass custom function

Sorted is very easy to use. We can use both built-in and custom function for sorting. Some example are given here. Remember it always return a new array by kipping the original array

a=["Life", "is", "very","easy", "with", "python"]

def myFunction(data):
    return data[0]

print sorted(a)
print sorted(a,key=myFunction)
print sorted(a,key=len)
print sorted(a)

Output:

['Life', 'easy', 'is', 'python', 'very', 'with']
['Life', 'easy', 'is', 'python', 'very', 'with']
['is', 'Life', 'very', 'easy', 'with', 'python']
['Life', 'easy', 'is', 'python', 'very', 'with']

python sorted: sort array

I like sorted because it is easy to use, sort multi structered data and also keep the original data which very important some times

 
a=[3,2,1,4,5]
print a
print sorted(a)
print sorted(a,reverse=True)
print a

Output:

[3, 2, 1, 4, 5]
[1, 2, 3, 4, 5]
[5, 4, 3, 2, 1]
[3, 2, 1, 4, 5]