AAE-NA-Labs/Direct Methods for Solving Linear Systems/Alg6_RREF.m

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function A = Alg6_RREF(A)
% Algorithm 6: Reduced Row Echelon Form (RREF)
% M rows, N columns
[M, N] = size(A);
n = 0;
for m = 1 : M
n = n + 1
if n > N
break
end
A
% We want the left-most coefficient to be 1 (pivot)
row = A(m, :);
if row(m) == 0
n = n + 1
end
[m ,n]
row = row/row(n);
A(m, :) = row;
for i = 1 : M
if i ~= m
A(i, :) = A(i, :)-(A(i, n))*row;
end
end
A
for i = m + 1 : M
A(i:end, m+1:end); % Partial matrix (in which we are looking for non-zero pivots)
A(i:end, m+1); % Left-most column
if ~any(A(i:end, m+1)) % If the left-most column has only zeros check the next one
m = m + 1;
end
A(i:end, m+1:end);
if A(i, m+1) == 0
non_zero_row = find(A(i:end,m+1), 1);
if isempty(non_zero_row)
continue
end
A([i, i+non_zero_row-1], :) = deal(A([i+non_zero_row-1, i], :));
end
end
end
end