@Mccamo

A = [2,1,-2;3,2,2;5,4,3]; b = [1;7;12];
A0 = A; b0 = b;
n = size(A,1);
I = eye(n);
k = 0;  %Initialise phase counter

k = k+1; % Reset/update phase counter
% Locate position of element largest modulus 
% in the pivot element
[~, r] = max(abs(A(k:n,k)));

# install.packages("pracma") # Only required if you haven't installed it before
# library(pracma)

A <- matrix(c(2, 1, -2, 3, 2, 2, 5, 4, 3), nrow = 3, byrow = TRUE)
b <- matrix(c(1, 7, 12), ncol = 1)
A0 <- A
b0 <- b
n <- nrow(A)
I <- diag(n)
k <- 0  # Initialize phase counter

import numpy as np

A0 = np.array([[3, 1, 4, -1],
               [2, -2, -1, 2],
               [5, 7, 14, 8],
               [1, 3, 2, 4]])

b0 = np.array([7, 1, 20, -4])

A = A0.copy()