function varargout = unique(varargin) 

%UNIQUE Set unique.

%   C = UNIQUE(A) for the array A returns the same values as in A but with 

%   no repetitions. C will be sorted.    

%  

%   C = UNIQUE(A,'rows') for the matrix A returns the unique rows of A.

%   The rows of the matrix C will be in sorted order.

%  

%   [C,IA,IC] = UNIQUE(A) also returns index vectors IA and IC such that

%   C = A(IA) and A = C(IC) (or A(:) = C(IC), if A is a matrix or array).  

%  

%   [C,IA,IC] = UNIQUE(A,'rows') also returns index vectors IA and IC such

%   that C = A(IA,:) and A = C(IC,:). 

%  

%   [C,IA,IC] = UNIQUE(A,OCCURRENCE) and

%   [C,IA,IC] = UNIQUE(A,'rows',OCCURRENCE) specify which index is returned

%   in IA in the case of repeated values (or rows) in A. The default value

%   is OCCURRENCE = 'first', which returns the index of the first occurrence 

%   of each repeated value (or row) in A, while OCCURRENCE = 'last' returns

%   the index of the last occurrence of each repeated value (or row) in A.

%  

%   [C,IA,IC] = UNIQUE(A,'stable') returns the values of C in the same order

%   that they appear in A, while [C,IA,IC] = UNIQUE(A,'sorted') returns the

%   values of C in sorted order. If A is a row vector, then C will be a row

%   vector as well, otherwise C will be a column vector. IA and IC are

%   column vectors. If there are repeated values in A, then IA returns the

%   index of the first occurrence of each repeated value.

% 

%   [C,IA,IC] = UNIQUE(A,'rows','stable') returns the rows of C in the same

%   order that they appear in A, while [C,IA,IC] = UNIQUE(A,'rows','sorted')

%   returns the rows of C in sorted order.

% 

%   The behavior of UNIQUE has changed.  This includes:

%     -	occurrence of indices in IA and IC switched from last to first

%     -	IA and IC will always be column index vectors

% 

%   If this change in behavior has adversely affected your code, you may 

%   preserve the previous behavior with:

% 

%        [C,IA,IC] = UNIQUE(A,'legacy')

%        [C,IA,IC] = UNIQUE(A,'rows','legacy') 

%        [C,IA,IC] = UNIQUE(A,OCCURRENCE,'legacy')

%        [C,IA,IC] = UNIQUE(A,'rows',OCCURRENCE,'legacy')

%

%   Examples:

%

%       a = [9 9 9 9 9 9 8 8 8 8 7 7 7 6 6 6 5 5 4 2 1]

%

%       [c1,ia1,ic1] = unique(a)

%       % returns

%       c1 = [1 2 4 5 6 7 8 9]

%       ia1 = [21 20 19 17 14 11 7 1]'

%       ic1 = [8 8 8 8 8 8 7 7 7 7 6 6 6 5 5 5 4 4 3 2 1]'

%

%       [c2,ia2,ic2] = unique(a,'stable')

%       % returns

%       c2 = [9 8 7 6 5 4 2 1]

%       ia2 = [1 7 11 14 17 19 20 21]'

%       ic2 = [1 1 1 1 1 1 2 2 2 2 3 3 3 4 4 4 5 5 6 7 8]'

%

%       c = unique([1 NaN NaN 2])

%       % NaNs compare as not equal, so this returns

%       c = [1 2 NaN NaN]

%

%   Class support for input A:

%      - logical, char, all numeric classes

%      - cell arrays of strings

%      -- 'rows' option is not supported for cell arrays

%      - objects with methods SORT (SORTROWS for the 'rows' option) and NE

%      -- including heterogeneous arrays

%

%   See also UNIQUETOL, INTERSECT, ISMEMBER, ISMEMBERTOL, UNION, SETDIFF,

%            SETXOR, SORT, SORTROWS.

%   Copyright 1984-2018 The MathWorks, Inc.

% Determine the number of outputs requested.

if nargout == 0 

    nlhs = 1;

else 

    nlhs = nargout; 

end 

narginchk(1,4); 

% Convert string flags to char flags to dispatch to the right method

if nargin > 1 

    hadStringArguments = false;

    for i = 2:nargin

        if isstring(varargin{i})

            varargin{i} = convertFlag(varargin{i});

            hadStringArguments = true;

        end

    end

    if hadStringArguments

        [varargout{1:nlhs}] = unique(varargin{:});

        return;

    end

end

nrhs = nargin; 

if nrhs == 1 

    [varargout{1:nlhs}] = uniqueR2012a(varargin{:}); 

else

    % acceptable combinations, with optional inputs denoted in []

    % unique(A, ['rows'], ['first'/'last'], ['legacy'/'R2012a']),

    % where the position of 'rows' and 'first'/'last' may be reversed

    % unique(A, ['rows'], ['sorted'/'stable']),

    % where the position of 'rows' and 'sorted'/'stable' may be reversed

    flagvals = ["rows" "first" "last" "sorted" "stable" "legacy" "R2012a"];

    % When a flag is found, note the index into varargin where it was found

    flaginds = zeros(1,length(flagvals));

    for i = 2:nrhs

        flag = varargin{i};

        assert(~isstring(flag))

        if ~ischar(flag)

            error(message('MATLAB:UNIQUE:UnknownInput'));

        end

        foundflag = startsWith(flagvals,flag,'IgnoreCase',true);

        if sum(foundflag) ~= 1

            error(message('MATLAB:UNIQUE:UnknownFlag',flag));

        end

        % Only 1 occurrence of each allowed flag value

        if flaginds(foundflag)

            error(message('MATLAB:UNIQUE:RepeatedFlag',flag));

        end

        flaginds(foundflag) = i;

    end

    % Only 1 of each of the paired flags

    if flaginds(2) && flaginds(3)

        error(message('MATLAB:UNIQUE:OccurrenceConflict'))

    end

    if flaginds(4) && flaginds(5)

        error(message('MATLAB:UNIQUE:SetOrderConflict'))

    end

    if flaginds(6) && flaginds(7)

        error(message('MATLAB:UNIQUE:BehaviorConflict'))

    end

    % 'legacy' and 'R2012a' flags must be trailing

    if flaginds(6) && flaginds(6)~=nrhs

        error(message('MATLAB:UNIQUE:LegacyTrailing'))

    end

    if flaginds(7) && flaginds(7)~=nrhs

        error(message('MATLAB:UNIQUE:R2012aTrailing'))

    end

    if flaginds(4) || flaginds(5) % 'stable'/'sorted' specified

        if flaginds(2) || flaginds(3) % does not combine with 'first'/'last'

            error(message('MATLAB:UNIQUE:SetOrderOccurrence'))

        end

        if flaginds(6) || flaginds(7) % does not combine with 'legacy'/'R2012a'

            error(message('MATLAB:UNIQUE:SetOrderBehavior'))

        end

        [varargout{1:nlhs}] = uniqueR2012a(varargin{1},logical(flaginds(1:5)));

    elseif flaginds(7) % trailing 'R2012a' specified

        [varargout{1:nlhs}] = uniqueR2012a(varargin{1},logical(flaginds(1:5)));

    elseif flaginds(6) % trailing 'legacy' specified

        [varargout{1:nlhs}] = uniquelegacy(varargin{1},logical(flaginds(1:3)));

    else % 'R2012a' (default behavior, to be changed to 'R2012a' in future)

        [varargout{1:nlhs}] = uniqueR2012a(varargin{1},logical(flaginds(1:5)));

    end

end 

end