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function b = gee_its_short (A, b)
%GEE_ITS_SHORT x=A\b, few comments, no error checking (just for line count)
% Example:
% x = gee_its_short (A,b) ; % same as x=A\b for square A
% See also: mldivide, gee_its_simple
% GEE, Copyright (c) 2006-2007, Timothy A Davis. All Rights Reserved.
% SPDX-License-Identifier: BSD-3-clause
n = size (A,1) ;
for k = 1:n
[x i] = max (abs (A (k:n,k))) ;
i = i+k-1 ;
A ([k i],:) = A ([i k],:) ;
b ([k i],:) = b ([i k],:) ;
A (k+1:n,k) = A (k+1:n,k) / A (k,k) ;
A (k+1:n,k+1:n) = A (k+1:n,k+1:n) - A (k+1:n,k) * A (k,k+1:n) ;
b (k+1:n,:) = b (k+1:n,:) - A (k+1:n,k) * b (k,:) ;
end
for k = n:-1:1
b (k,:) = b (k,:) / A (k,k) ;
b (1:k-1,:) = b (1:k-1,:) - A (1:k-1,k) * b (k,:) ;
end
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