Welcome folks today in this blog post we will be sorting number array in ascending or descending order using radix sort algorithm in python. All the full source code of the application is shown below.

Get Started

In order to get started you need to make an app.py file and copy paste the following code

app.py

# Python program for implementation of Radix Sort
    
# A function to do counting sort of arr[] according to
# the digit represented by exp.
def countingSort(arr, exp1):
    
    n = len(arr)
    
    # The output array elements that will have sorted arr
    output = [0] * (n)
    
    # initialize count array as 0
    count = [0] * (10)
    
    # Store count of occurrences in count[]
    for i in range(0, n):
        index = (arr[i]/exp1)
        count[int((index)%10)] += 1
    
    # Change count[i] so that count[i] now contains actual
    # position of this digit in output array
    for i in range(1,10):
        count[i] += count[i-1]
    
    # Build the output array
    i = n-1
    while i>=0:
        index = (arr[i]/exp1)
        output[ count[ int((index)%10) ] - 1] = arr[i]
        count[int((index)%10)] -= 1
        i -= 1
    
    # Copying the output array to arr[],
    # so that arr now contains sorted numbers
    i = 0
    for i in range(0,len(arr)):
        arr[i] = output[i]

# Method to do Radix Sort
def radixSort(arr):

    # Find the maximum number to know number of digits
    max1 = max(arr)

    # Do counting sort for every digit. Note that instead
    # of passing digit number, exp is passed. exp is 10^i
    # where i is current digit number
    exp = 1
    while max1/exp > 0:
        countingSort(arr,exp)
        exp *= 10

# Driver code to test above
arr = [ 170, 45, 75, 90, 802, 24, 2, 66]
radixSort(arr)

for i in range(len(arr)):
    print(arr[i]),

# This code is contributed by Mohit Kumra
# This code is updated by Sudeep Saxena(saxenasudeepcse@gmail.com) on July 9, 2020

Now if you execute the python file script by typing the below command as shown below

python app.py