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62 lines
1.3 KiB
Matlab
62 lines
1.3 KiB
Matlab
function x = gaussianElimination(A, b) % A - matrix, b - vector
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[~, Height] = size(A);
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% Find column with greatest value element
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for i = 1 : Height - 1
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m = max(A(i:Height, i));
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% Find row with greatest value element
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for k = i : Height
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if A(k, i) == m % If the element has the biggest value we now
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% have the value of two rows that we want to swap
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% Swap row in matrix A %
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swapRow(A, i, k);
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swapValue(b, i, k);
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break;
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end % end if
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end % end for
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% Swap value in vector B %
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end % end for
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for j = i + 1 : Height
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l = A(j, i) / A(i, i);
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b(j, 1) = b(j, 1) - l * b(i, 1);
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for t = 1 : Height
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A(j, t) = A(j, t) - l * A(i, t);
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end % end for
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end % end for
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x = zeros(Height, 1);
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for k = Height: -1:1
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E = 0;
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for iter = k + 1 : Height
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E = E + A(k, iter) * x(iter, 1);
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end
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x(k, 1) = (b(k, 1) - E) / A(k, k);
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end
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end % end function
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function swapRow(A, j, k)
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temp = A(j, :);
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A(j, :) = A(k, :);
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A(k, :) = temp;
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end % end function
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function swapValue(b, j, k)
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temp = b(j);
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b(j) = b(k);
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b(k) = temp;
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end % end function
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