Added source Matlab code for reference

matlab/linkage/myCell2mat.m

@@ -0,0 +1,120 @@
+function m = myCell2mat(c)
+%CELL2MAT Convert the contents of a cell array into a single matrix.
+%   M = CELL2MAT(C) converts a multidimensional cell array with contents of
+%   the same data type into a single matrix. The contents of C must be able
+%   to concatenate into a hyperrectangle. Moreover, for each pair of
+%   neighboring cells, the dimensions of the cell's contents must match,
+%   excluding the dimension in which the cells are neighbors. This constraint
+%   must hold true for neighboring cells along all of the cell array's
+%   dimensions.
+%
+%   The dimensionality of M, i.e. the number of dimensions of M, will match
+%   the highest dimensionality contained in the cell array.
+%
+%   CELL2MAT is not supported for cell arrays containing cell arrays or
+%   objects.
+%
+%	Example:
+%	   C = {[1] [2 3 4]; [5; 9] [6 7 8; 10 11 12]};
+%	   M = cell2mat(C)
+%
+%	See also MAT2CELL, NUM2CELL
+
+% Copyright 1984-2006 The MathWorks, Inc.
+% $Revision: 1.10.4.6 $  $Date: 2006/06/20 20:09:38 $
+
+% Error out if there is no input argument
+if nargin==0
+    error('MATLAB:cell2mat:NoInputs',['No input argument specified. ' ...
+        'There should be exactly one input argument.'])
+end
+% short circuit for simplest case
+elements = numel(c);
+if elements == 0
+    m = [];
+    return
+end
+if elements == 1
+    if isnumeric(c{1}) || ischar(c{1}) || islogical(c{1}) || isstruct(c{1})
+        m = c{1};
+        return
+    end
+end
+% Error out if cell array contains mixed data types
+cellclass = class(c{1});
+ciscellclass = cellfun('isclass',c,cellclass);
+if ~all(ciscellclass(:))
+    error('MATLAB:cell2mat:MixedDataTypes', ...
+        'All contents of the input cell array must be of the same data type.');
+end
+
+% Error out if cell array contains any cell arrays or objects
+ciscell = iscell(c{1});
+cisobj = isobject(c{1});
+if cisobj || ciscell
+    error('MATLAB:cell2mat:UnsupportedCellContent',['Cannot support cell ' ...
+        'arrays containing cell arrays or objects.']);
+end
+
+% If cell array of structures, make sure the field names are all the same
+if isstruct(c{1})
+    cfields = cell(elements,1);
+    for n=1:elements
+        cfields{n} = fieldnames(c{n});
+    end
+    % Perform the actual field name equality test
+    if ~isequal(cfields{:})
+        error('MATLAB:cell2mat:InconsistentFieldNames', ...
+            ['The field names of each cell array element must be consistent ' ...
+            'and in consistent order.'])
+    end
+end
+
+% If cell array is 2-D, execute 2-D code for speed efficiency
+if ndims(c) == 2
+    rows = size(c,1);
+    m = cell(rows,1);
+    % Concatenate each row first
+    for n=1:rows
+        m{n} = cat(3,c{n,:});
+    end
+    % Now concatenate the single column of cells into a matrix
+    m = cat(3,m{:});
+    return
+end
+
+csize = size(c);
+% Treat 3+ dimension arrays
+
+% Construct the matrix by concatenating each dimension of the cell array into
+%   a temporary cell array, CT
+% The exterior loop iterates one time less than the number of dimensions,
+%   and the final dimension (dimension 1) concatenation occurs after the loops
+
+% Loop through the cell array dimensions in reverse order to perform the
+%   sequential concatenations
+for cdim=(length(csize)-1):-1:1
+    % Pre-calculated outside the next loop for efficiency
+    ct = cell([csize(1:cdim) 1]);
+    cts = size(ct);
+    ctsl = length(cts);
+    mref = {};
+
+    % Concatenate the dimension, (CDIM+1), at each element in the temporary cell
+    %   array, CT
+    for mind=1:prod(cts)
+        [mref{1:ctsl}] = ind2sub(cts,mind);
+        % Treat a size [N 1] array as size [N], since this is how the indices
+        %   are found to calculate CT
+        if ctsl==2 && cts(2)==1
+            mref = {mref{1}};
+        end
+        % Perform the concatenation along the (CDIM+1) dimension
+        ct{mref{:}} = cat(cdim+1,c{mref{:},:});
+    end
+    % Replace M with the new temporarily concatenated cell array, CT
+    c = ct;
+end
+
+% Finally, concatenate the final rows of cells into a matrix
+m = cat(1,c{:});