Passing a structure from GUI to a function

Hello, I created a GUI that generates a multi-field structure which is passed as an argument to a function (in a separated m file) selected by the user. It worked well for a while, but now every time I run the GUI, when the selected function is executed it fails to receive the intended structure. The structure looks fine before it is passed to the function, but when I check the function's varargin it says '[1x1 struct]', and obviously it doesn't preserve any of the fields of the original struct (when I try to access any such field I get an 'Attempt to reference field of non-structure array' error).

Bellow is the piece of code from the GUI (a callback function associated with a push button) that generates the structure (designParams) and calls the user-selected function (filename). The specific function I call has the header: function dataAnalysis (varargin)

Any idea what I'm doing wrong? Thanks,

Chen

    % --- Executes on button press in runButton.
    function runButton_Callback(hObject, eventdata, handles)
    % hObject    handle to runButton (see GCBO)
    % eventdata  reserved - to be defined in a future version of MATLAB
    % handles    structure with handles and user data (see GUIDATA)

    % Get parameter values
    designParams.titleFontSize = str2double(get (handles.titleFontSizeValue,'String'));
    designParams.axesFontSize = str2double(get (handles.axesFontSizeValue,'String'));
    designParams.tickFontSize = str2double(get (handles.tickFontSizeValue,'String'));
    designParams.labelFontSize = str2double(get (handles.labelFontSizeValue,'String'));
    designParams.fontType = get (handles.fontTypeValue,'String');
    designParams.figureUnits = get (handles.figureUnitsValue,'String');
    designParams.globalFigDim = get (handles.globalFigDim,'Value');
    designParams.figureHeight = str2double(get (handles.figureHeightValue,'String'));
    designParams.figureWidth = str2double(get (handles.figureWidthValue,'String'));
    designParams.globalYScale = get (handles.globalYScale,'Value');
    designParams.keepTitles = get (handles.keepTitles,'Value');
    designParams.addDataLabel = get (handles.addDataLabels,'Value');
    designParams.addLegend = get (handles.addLegend,'Value');
    designParams.askFolder = get (handles.askFolder,'Value');
    for colorInd=1:5
        RColor= strcat('str2double(get (handles.RColor',num2str(colorInd),',''String''))');
        GColor= strcat('str2double(get (handles.GColor',num2str(colorInd),',''String''))');
        BColor= strcat('str2double(get (handles.BColor',num2str(colorInd),',''String''))');
        designParams.colors(colorInd,1)=eval(RColor);
        designParams.colors(colorInd,2)=eval(GColor);
        designParams.colors(colorInd,3)=eval(BColor);
    end
    designParams.colors = designParams.colors/255;

    % Open function for data analysis
    filename = uigetfile ('*.m','Select the MATLAB code file');
    [pathstr,name,ext] = fileparts(filename);
    filename = str2func(name);

    filename (designParams);

Answer 1

[Image Analyst]

You forgot to show the code in the callback where you're actually calling dataAnalysis() and passing designParams to it.

If in dataAnalysis, it says that the input is a struct 1x1 that doesn't mean it has no fields. It will have fields. Just try this

a.f = 10;
whos a

See? So the fieldnames are probably not what you're using. Perhaps the capitalization is wrong. What does this say in dataAnalysis

filenames(varargin{1})

This will list all the field names of the first argument.

[Image Analyst]

Chen's "Answer" moved here since it's not an "Answer" to the original question but a reply to me:

Thank you for the answer. Actually the code I submitted did include calling the destination function - I ask the user to select an m file and use its name as a function name:

    % Open function for data analysis
    filename = uigetfile ('*.m','Select the MATLAB code file');
    [pathstr,name,ext] = fileparts(filename);
    filename = str2func(name);

    filename (designParams);

This code does run the desired function, but the structure itself is not passed as I expected. If I try to pass other types of arguments (e.g. double) to the function they are passed correctly. I typed whos designParams in the callback function and got:

Name Size Bytes Class Attributes

designParams      1x1              2892  struct

But when I typed whos varargin in dataAnalysis I got:

 Name          Size            Bytes  Class    Attributes

varargin      1x1              3004  cell

If it preserved the desired information I don't know how to access it. Any advice?

[Image Analyst]

Well of course varargin is a cell - we know that. You need to extract the variable from the varargin cell array first. What does this say in dataAnalysis:

fprintf('Number of arguments = %d\n', nargin);
dp = varargin{1} % Extract designParams from the first cell
whos dp % Show infomation about it.