function I = argmax(X, DIM)
%ARGMAX Argument of the maximum
% For vectors, ARGMAX(X) is the indix of the smallest element in X. For matrices,
% MAX(X) is a row vector containing the indices of the smallest elements from each
% column. This function is not supported for N-D arrays with N > 2.
%
% It is an efficient replacement to the use of [Y,I] = MAX(X,[],DIM);
% See ARGMAX_DEMO for a speed comparison.
%
% I = ARGMAX(X,DIM) operates along the dimension DIM (DIM can be
% either 1 or 2).
%
% When complex, the magnitude ABS(X) is used, and the angle
% ANGLE(X) is ignored. This function cannot handle NaN's.
%
% Example:
% clc
% disp('If X = [2 8 4; 7 3 9]');
% disp('then argmax(X,1) should be [2 1 2]')
% disp('while argmax(X,2) should be [2 3]''. Now we check it:')
% disp(' ');
% X = [2 8 4;
% 7 3 9]
% argmax(X,1)
% argmax(X,2)
%
% See also ARGMIN, ARGMAXMIN_MEX, ARGMAX_DEMO, MIN, MAX, MEDIAN, MEAN, SORT.
% Copyright Marco Cococcioni, 2009.
% $Revision: 1.0 $ $Date: 2009/02/16 19:24:01$
if nargin < 2,
DIM = 1;
end
if length(size(X)) > 2,
error('Function not provided for N-D arrays when N > 2.');
end
if (DIM ~=1 && DIM ~= 2),
error('DIM has to be either 1 or 2');
end
if any(isnan(X(:))),
error('Cannot handle NaN''s.');
end
if not(isreal(X)),
X = abs(X);
end
max_NOT_MIN = 1; % computes argmax
I = argmaxmin_mex(X, DIM, max_NOT_MIN);
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