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Create local repository for matrix toolboxes. Step #0 done.
author Antonio Pino Robles <data.script93@gmail.com>
date Wed, 06 May 2015 14:56:53 +0200
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8f23314345f4 Create local repository for matrix toolboxes. Step #0 done.
Antonio Pino Robles <data.script93@gmail.com>
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1 function x = gj(A, b, piv)
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2 %GJ Gauss-Jordan elimination to solve Ax = b.
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3 % x = GJ(A, b, PIV) solves Ax = b by Gauss-Jordan elimination,
8f23314345f4 Create local repository for matrix toolboxes. Step #0 done.
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4 % where A is a square, nonsingular matrix.
8f23314345f4 Create local repository for matrix toolboxes. Step #0 done.
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5 % PIV determines the form of pivoting:
8f23314345f4 Create local repository for matrix toolboxes. Step #0 done.
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6 % PIV = 0: no pivoting,
8f23314345f4 Create local repository for matrix toolboxes. Step #0 done.
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7 % PIV = 1 (default): partial pivoting.
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9 n = max(size(A));
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10 if nargin < 3, piv = 1; end
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11
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12 for k=1:n
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13 if piv
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14 % Partial pivoting (below the diagonal).
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15 [colmax, i] = max( abs(A(k:n, k)) );
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16 i = k+i-1;
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17 if i ~= k
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18 A( [k, i], : ) = A( [i, k], : );
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19 b( [k, i] ) = b( [i, k] );
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20 end
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21 end
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23 irange = [1:k-1 k+1:n];
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24 jrange = k:n;
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25 mult = A(irange,k)/A(k,k); % Multipliers.
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26 A(irange, jrange) = A(irange, jrange) - mult*A(k, jrange);
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27 b(irange) = b(irange) - mult*b(k);
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29 end
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8f23314345f4 Create local repository for matrix toolboxes. Step #0 done.
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31 x = diag(diag(A))\b;