ComputerNetworksPythonPractical/hamming.py at master · sagarmakar/ComputerNetworksPythonPractical · GitHub

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def hammingsenodd(inp):
    data=list(inp)
    data.reverse()
    c,ch,j,r,h=0,0,0,0,[]

    while len(inp)+r+1>pow(2,r):
        r=r+1

    for i in range(0,r+len(data)):
        p=2**c

        if p==(i+1):
            h.append(0)
            c=c+1

        else:
            h.append(int(data[j]))
            j=j+1

    for parity in range(0,(len(h))):
        ph=(2**ch)
        if ph==(parity+1):
            startIndex=ph-1
            i=startIndex
            toXor=[]

            while i<len(h):
                block=h[i:i+ph]
                toXor.extend(block)
                i+=2*ph

            for z in range(1,len(toXor)):
                h[startIndex]=h[startIndex]^toXor[z]
            ch+=1

    h.reverse()
    print('Hamming code generated would be:- ', end="")
    print(int(''.join(map(str, h))))


def hammingrecodd(inp):
    data=list(inp)
    data.reverse()
    c,ch,j,r,error,h,parity_list,h_copy=0,0,0,0,0,[],[],[]

    for k in range(0,len(data)):
        p= 2**c
        h.append(int(data[k]))
        h_copy.append(data[k])
        if p==(k+1):
            c=c+1

    for parity in range(0,len(h)):
        ph=2**ch
        if ph==(parity+1):

            startIndex=ph-1
            i=startIndex
            toXor=[]

            while i<len(h):
                block=h[i:i+ph]
                toXor.extend(block)
                i+=2*ph

            for z in range(1,len(toXor)):
                h[startIndex]=h[startIndex]^toXor[z]
            parity_list.append(h[parity])
            ch+=1
    parity_list.reverse()
    error=sum(int(parity_list) * (2 ** i) for i, parity_list in enumerate(parity_list[::-1]))

    if((error)==0):
        print('There is no error in the hamming code received')

    elif((error)>=len(h_copy)):
        print('Error cannot be detected')

    else:
        print('Error is in',error,'bit')

        if(h_copy[error-1]=='0'):
            h_copy[error-1]='1'

        elif(h_copy[error-1]=='1'):
            h_copy[error-1]='0'
        print('After correction hamming code is:- ')
        h_copy.reverse()
        print(int(''.join(map(str, h_copy))))

def hammingseneven(inp):
    data=list(inp)
    data.reverse()
    c,ch,j,r,h=0,0,0,0,[]

    while (len(inp)+r+1)>(pow(2,r)):
        r=r+1

    for i in range(0,r+len(data)):
        p=2**c

        if(p==(i+1)):
            h.append(0)
            c=c+1

        else:
            h.append(int(data[j]))
            j=j+1

    for parity in range(0,len(h)):
        ph=2**ch
        if ph==(parity+1):
            startIndex=ph-1
            i=startIndex
            toXor=[]

            while i<len(h):
                block=h[i:i+ph]
                toXor.extend(block)
                i+=ph

            for z in range(1,len(toXor)):
                h[startIndex]=h[startIndex]^toXor[z]
            ch+=1

    h.reverse()
    print('Hamming code generated would be:- ', end="")
    print(int(''.join(map(str, h))))


def hammingreceven(inp):
    data=list(inp)
    data.reverse()
    c,ch,j,r,error,h,parity_list,h_copy=0,0,0,0,0,[],[],[]

    for k in range(0,len(data)):
        p=2**c
        h.append(int(data[k]))
        h_copy.append(data[k])
        if p==(k+1):
            c=c+1

    for parity in range(0,len(h)):
        ph=2**ch
        if ph==(parity+1):

            startIndex=ph-1
            i=startIndex
            toXor=[]

            while i<len(h):
                block=h[i:i+ph]
                toXor.extend(block)
                i+=ph

            for z in range(1,len(toXor)):
                h[startIndex]=h[startIndex]^toXor[z]
            parity_list.append(h[parity])
            ch+=1
    parity_list.reverse()
    error=sum(int(parity_list) * (2 ** i) for i, parity_list in enumerate(parity_list[::-1]))

    if error==0:
        print('There is no error in the hamming code received')

    elif error>=len(h_copy):
        print('Error cannot be detected')

    else:
        print('Error is in',error,'bit')

        if h_copy[error-1]=='0' :
            h_copy[error-1]='1'

        elif h_copy[error-1]=='1' :
            h_copy[error-1]='0'
        print('After correction hamming code is:- ')
        h_copy.reverse()
        print(int(''.join(map(str, h_copy))))

input1=int(input("Choose 1 for even and 2 for odd HAMMING error detection: "))
if input1==1:
    input2= int(input("choose 1 for sender side and 2 for receiver side: \n"))
    if input2 == 1:
        hammingseneven(input("enter your data binary string to send here: "))
    elif input2 == 2:
        hammingreceven(input("enter your data binary string to send here: "))
    else: print("please enter a valid data.")


elif input1==2:
    input2= int(input("choose 1 for sender side and 2 for receiver side: \n"))
    if input2 == 1:
        hammingsenodd(input("enter your data binary string to send here: "))
    elif input2 == 2:
        hammingrecodd(input("enter your data binary string to send here: "))
    else: print("please enter a valid data.")

else: print("enter valid data.")