function str = printstruct(name, val, varargin)

% PRINTSTRUCT converts a MATLAB structure into a multiple-line string that, when

% evaluated by MATLAB, results in the original structure. It also works for most

% other standard MATLAB classes, such as numbers, vectors, matrices, and cell-arrays.

%

% Use as

% str = printstruct(val)

% or

% str = printstruct(name, val)

% where "val" is any MATLAB variable, e.g. a scalar, vector, matrix, structure, or

% cell-array. If you pass the name of the variable, the output is a piece of MATLAB code

% that you can execute, i.e. an ASCII serialized representation of the variable.

%

% Example

% a.field1 = 1;

% a.field2 = 2;

% s = printstruct(a)

%

% b = rand(3);

% s = printstruct(b)

%

% s = printstruct('c', randn(10)>0.5)

%

% See also DISP, NUM2STR, INT2STR, MAT2STR

% Copyright (C) 2006-2023, Robert Oostenveld

%

% This file is part of FieldTrip, see http://www.fieldtriptoolbox.org

% for the documentation and details.

%

% FieldTrip is free software: you can redistribute it and/or modify

% it under the terms of the GNU General Public License as published by

% the Free Software Foundation, either version 3 of the License, or

% (at your option) any later version.

%

% FieldTrip is distributed in the hope that it will be useful,

% but WITHOUT ANY WARRANTY; without even the implied warranty of

% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

% GNU General Public License for more details.

%

% You should have received a copy of the GNU General Public License

% along with FieldTrip. If not, see <http://www.gnu.org/licenses/>.

%

% $Id$

if nargin==1

val = name;

name = inputname(1);

end

% get the options and set defaults

transposed = ft_getopt(varargin, 'transposed', false); % print a column as a transposed row, or a row as a transposed column

linebreaks = ft_getopt(varargin, 'linebreaks', true); % print with or without linebreaks

lastnewline = ft_getopt(varargin, 'lastnewline', false); % end with a newline

lastsemicolon = ft_getopt(varargin, 'lastsemicolon', true); % end with a semicolon

% when called recursively, it should keep the last newline and semicolon intact

varargin = ft_setopt(varargin, 'lastnewline', true);

varargin = ft_setopt(varargin, 'lastsemicolon', true);

% Note that because we don't know the final size of the string, iteratively appending

% is actually faster than creating a cell-array and subsequently doing a cat(2,

% strings{:}). Note also that sprintf() is slow.

str = '';

% Note further that in the string concatenations I use the numerical value

% of a newline (\n), which is 10.

if numel(val) == 0

if iscell(val)

str = [name ' = {};' 10];

elseif isstruct(val)

str = [name ' = [];' 10];

elseif isnumeric(val)

str = [name ' = [];' 10];

end

elseif isstruct(val)

if numel(val)>1

% print it as a struct-array

str = cell(size(val));

for i=1:numel(val)

str{i} = printstruct(sprintf('%s(%d)', name, i), val(i), varargin{:});

end

str = cat(2, str{:});

elseif numel(val)==1

% print it as a named structure

fn = fieldnames(val);

for i=1:length(fn)

fv = val.(fn{i});

switch class(fv)

case {'char' 'string'}

line = printstr([name '.' fn{i}], fv, linebreaks, transposed);

case {'single' 'double' 'int8' 'int16' 'int32' 'int64' 'uint8' 'uint16' 'uint32' 'uint64' 'logical'}

if ismatrix(fv)

line = printmat([name '.' fn{i}], fv, linebreaks, transposed);

else

ft_warning('multidimensional arrays are not supported');

line = [name '.' fn{i} ' = []; % ERROR: multidimensional arrays are not supported.'];

end

case 'cell'

line = printcell([name '.' fn{i}], fv, linebreaks, transposed);

case 'struct'

line = [printstruct([name '.' fn{i}], fv, varargin{:}) 10];

case 'function_handle'

line = printstr([name '.' fn{i}], func2str(fv), linebreaks, transposed);

case 'table'

ft_warning('tables are not supported');

line = [name '.' fn{i} ' = []; % ERROR: tables are not supported.'];

otherwise

ft_error('unsupported');

end

str = [str line newline];

end % for fieldnames

if isempty(fn)

% print it as an empty structure

str = [name ' = struct();'];

end

end

elseif ~isstruct(val)

% print it as a named variable

switch class(val)

case {'char' 'string'}

str = printstr(name, val, linebreaks, transposed);

case {'double' 'single' 'int8' 'int16' 'int32' 'int64' 'uint8' 'uint16' 'uint32' 'uint64' 'logical'}

str = printmat(name, val, linebreaks, transposed);

case 'cell'

str = printcell(name, val, linebreaks, transposed);

case 'table'

ft_warning('tables are not supported');

str = [name ' = []; % ERROR: tables are not supported.'];

otherwise

ft_error('unsupported');

end

end

% replace double newlines with a single one

str = strrep(str, [newline newline], newline);

if isempty(name)

% remove the ' = ' part from the string

str = str(4:end);

end

if str(end)==newline && ~lastnewline

% remove the last newline

str = str(1:end-1);

end

if str(end)==';' && ~lastsemicolon

% remove the last semicolon

str = str(1:end-1);

end

if ~nargout

disp(str)

clear str

end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

function str = printstr(name, val, linebreaks, transposed)

siz = size(val);

if siz(1)>1

str = sprintf('%s = \n', name);

for i=1:siz(1)

str = [str sprintf(' %s\n', printval(val(i,:), linebreaks, transposed))];

end

elseif siz(1)==1

str = sprintf('%s = %s;\n', name, printval(val, linebreaks, transposed));

else

str = sprintf('%s = '''';\n', name);

end

if ~linebreaks

str(str==10) = [];

end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

function str = printcell(name, val, linebreaks, transposed)

siz = size(val);

if isempty(val)

str = sprintf('%s = {};\n', name);

elseif numel(siz) == 2 && siz(2) == 1 && transposed

% print column vector as (non-conjugate) transposed row

str = printcell(name, transpose(val), linebreaks, false);

str = sprintf('%s'';\n', str(1:end-2));

elseif numel(siz) == 2 && siz(1) == 1 && transposed

% print row vector as (non-conjugate) transposed column

str = printcell(name, transpose(val), linebreaks, false);

str = sprintf('%s'';\n', str(1:end-2));

else

str = sprintf('%s = {\n', name);

for i=1:siz(1)

for j=1:(siz(2)-1)

dum = printval(val{i,j}, linebreaks, transposed);

if endsWith(dum, ';')

dum = dum(1:end-1);

elseif endsWith(dum, [';' newline])

dum = dum(1:end-2);

end

str = [str ' ' dum ',']; % add the element with a comma

end

dum = printval(val{i,siz(2)}, linebreaks, transposed);

if endsWith(dum, ';')

dum = dum(1:end-1);

elseif endsWith(dum, [';' newline])

dum = dum(1:end-2);

end

str = [str ' ' dum 10]; % add the last element of each row with a linebreak

end

if siz(1)==1

str(str==10) = [];

end

str = sprintf('%s };\n', str);

end

if ~linebreaks

str(str==10) = [];

end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

function str = printmat(name, val, linebreaks, transposed)

siz = size(val);

if numel(val) == 0

str = sprintf('%s = [];\n', name);

elseif numel(val) == 1

if isa(val, 'double')

% an integer will never get trailing decimals when using %g

str = sprintf('%s = %g;', name, val);

elseif isa(val, 'logical') && val

str = sprintf('%s = true;', name);

elseif isa(val, 'logical') && ~val

str = sprintf('%s = false;', name);

else

str = sprintf('%s = %s(%g);', name, class(val), val);

end

elseif numel(siz) == 2 && siz(2) == 1 && transposed

% print column vector as (non-conjugate) transposed row

str = printmat(name, transpose(val), linebreaks, false);

str = sprintf('%s''', str);

elseif numel(siz) == 2 && siz(1) == 1 && transposed

% print row vector as (non-conjugate) transposed column

str = printmat(name, transpose(val), linebreaks, false);

str = sprintf('%s''', str);

elseif ismatrix(val)

if isa(val, 'double')

str = sprintf('%s = %s;', name, mat2str(val));

else

% add class information for non-double numeric matrices

str = sprintf('%s = %s;', name, mat2str(val, 'class'));

end

% add a newline after each semicolon

str = strrep(str, ';', [';' newline]);

else

ft_warning('multidimensional arrays are not supported');

str = [name ' = []; % ERROR: multidimensional arrays are not supported.'];

end

if ~linebreaks

str(str==10) = [];

end

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

function str = printval(val, linebreaks, transposed)

switch class(val)

case 'char'

str = ['''' val ''''];

case 'string'

% these use " in the declaration rather than '

str = ['"' char(val) '";'];

case {'single' 'double' 'int8' 'int16' 'int32' 'int64' 'uint8' 'uint16' 'uint32' 'uint64' 'logical'}

str = printmat('', val, linebreaks, transposed);

str = str(4:end);

if endsWith(str, ';')

str = str(1:end-1);

end

case 'function_handle'

str = ['@' func2str(val)];

case 'struct'

% print it as an anonymous structure

str = 'struct(';

fn = fieldnames(val);

for i=1:numel(fn)

str = [str '''' fn{i} '''' ', ' printval(val.(fn{i}), linebreaks, transposed)];

end

str = [str ')'];

otherwise

ft_error('unsupported');

end

if ~linebreaks

str(str==10) = [];

end