I am getting error messages when starting MatLab

I am not sure if there was a Windows update preceding this. However, re-installing MatLab did not change, i still got these error messages. I am getting these since i wanted to use the FlyFly toolbox https://hoverflyvision.weebly.com/software.html.These are the error messages i get:

"Dot indexing is not supported for variables of this type.

Error in settings>settings_OpeningFcn (line 73)

index = navData.activeStim;

Error in gui_mainfcn (line 220)

feval(gui_State.gui_OpeningFcn, gui_hFigure, [], guidata(gui_hFigure), varargin{:});

Error in settings (line 46)

[varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});

Error in matlab.internal.codingui.warmupProgrammingAids"

Answer 1

[ag]

Hi Fabian,

The error message "Dot indexing is not supported for variables of this type" typically occurs when attempting to access a field in a variable that is either not a structure or the respective field name does not exist within the structure.

To resolve this issue, you should first verify that the field exists within the structure variable before attempting to access it. The following code snippet illustrates how to achieve this:

if(isfield(navData, 'activeStim')) %here navData is the structure name, and activeStim is the field name
    %rest of the code
end

For more details, please refer to the following MathWorks documentation: https://www.mathworks.com/help/matlab/ref/isfield.html.

Hope this helps!

[Voss]

"or the respective field name does not exist within the structure"

That situation would produce a different error ("Unrecognized field name ...").

[Walter Roberson]

"Dot indexing is not supported for variables of this type" often (but not always) means that the underlying variable was unexpectedly assigned the null value, [ ]

Answer 2

[Steven Lord]

It seems like that software included a function (an app) named settings. That conflicts with the settings function in MATLAB introduced in release R2018a. That app will need to be renamed.

[Steven]

Many thanks Steven Lord (I remember the name from my MATLAB USENET days). Same issue here. I had a simple Simulink model in my startig directory that I'd names "settings.slx".