Lab 3: Solution of System of Linear Equations using Gauss Elimination with Partial Pivoting

import numpy as np
from math import *

n=int(input("No. of Unknowns:"))
A=np.zeros((n,n+1),dtype=float)
print("Enter the elements row-wise:")
for i in range(n):
    rowData=input(f"Row{i+1}:").split()
    if len(rowData)!=(n+1):
        raise Exception("Error in row and column")
    A[i]=np.array(rowData,dtype=float)

n=A.shape[0]
for j in range(n-1):
    k=np.argmax(np.abs(A[j:,j]))+j
    if k!=j:
        A[[j,k]]=A[[k,j]]
    
    if abs(A[j,j])<5e-8:
          raise Exception("Error in Pivoting")
          

    for i in range(j+1,n):
        A[i]=A[i]-A[i,j]/A[j,j]*A[j]

print("After Pivoting:")
print(np.round(A,2))

x=np.zeros(n,dtype=float)
for i in range(n-1,-1,-1):
    x[i]=(A[i,n]-np.sum(A[i,i+1:n]*x[i+1:n]))/A[i,i]
    
print("Solution is:=",x)