MATLAB: R2016b Diagnostic Viewer incorrectly displays warning messages containing a newline character

simulink

We issue warning messages in .m files which are executed in the Simulink build process (via a customized target that is based on grt).

The messages are displayed in the Diagnostic Viewer.

If the warning message contains a newline character (\n) then the diagnostic viewer displays the message including line breaks, but it doesn’t present it as warning (i.e. orange line at left border is expected) but only as info message (i.e. with blue/gray line). Other special characters work fine, and the same code executed with Simulink 2016a works fine.

The same code executed directly in the MATLAB console window also works, even with R2016b.

This is reproducible by adding any of these warnings to the ert_make_rtw_hook.m file or any m-file within the Simulink build process:

warning ('A:B', 'without line break results in correct display as warning');
warning ('A:B' ,'Should display as warning with line break \n but displays only as info with line break');
warning ('A:B' ,'Should display as warning with line break \n but displays only as info with line break. Hint from help (include more than one input argument like %d) has no effect.', 99);

Any similar use of the "warning" function produces the same result, e.g.:

warning('mywarn:noLineBreaks', 'without line break results in correct display as warning');
warning('mywarn:charLineBreak',['With character specification for line break' char(10) 'we also do not get a warning']);
warning('mywarn:nLineBreak','With newline specification for line break \n we also do not get a warning');
warning('mywarn:formatSpec','With format specification for line break %s we just get the character','\n');
warning('mywarn:formatSpec','With format specification for char(10) %s we also do not get a warning',char(10));

Best Answer

As a workaround, one can use the following syntax instead of using the "warning" function:

>> message = sprintf('With newline specification for line break \n we also do not get a warning');
>> sldiagviewer.reportWarning(message);

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MATLAB: How to apply font options when using the LaTeX interpreter in MATLAB

Note that the LaTeX processor included in MATLAB is primarily designed for creating mathematical expressions, meaning that some functionality related to fonts or document processing is not supported. However, some LaTeX commands can still be used to provide a great deal of customization, as shown in the example below.

Executing the following code will generate the figure shown below:

>> figure
>> strx = ['$t$'];
>> stry = ['$\dot{x}(t)$'];
>> xlabel(strx,'FontSize',30,'Interpreter','LaTeX','Color','r') % Font size/color is set using 'FontSize' and 'Color' name-value pairs
>> ylabel(stry,'FontSize',30,'Interpreter','LaTeX','Color','b')

The font style of the labels can be changed by applying certain LaTeX commands to "strx" and "stry". Note that some commands cannot be applied to the whole string, as the '\dot' character is not compatible. The following code shows how to implement a portion of the available options in MATLAB:

% 1) Serif (default), no italics
strx = ['$\textrm{t}$'];
stry = ['$\dot{\textrm{x}}(\textrm{t})$'];
% 2) Sans-serif, no italics
strx = ['$\textsf{t}$'];
stry = ['$\dot{\textsf{x}}(\textsf{t})$'];
% 3) Bold, no italics 
strx = ['$\textbf{t}$']; 
stry = ['$\dot{\textbf{x}}(\textbf{t})$'];
% 4) Bold and italic
strx = ['$\textbf{\textit{t}}$'];
stry = ['$\dot{\textbf{\textit{x}}}(\textbf{\textit{t}})$'];
% 5) Underlined, italic
strx = ['$\underline{t}$'];
stry = ['$\underline{\dot{x}(t)}$'];
% 6) Underlined, sans-serif (removes italic)
strx = ['$\underline{\textsf{t}}$'];
stry = ['$\underline{\dot{\textsf{x}}(\textsf{t})}$'];

Note that the following warning (or similar) may be generated when using the sans-serif options:

Warning: Error updating Text.
    Font cmss10 is not supported.

This occurs when using the LaTeX interpreter for sans-serif fonts and should not be of any concern. If you wish to suppress the display of this warning, please visit the link below:

https://www.mathworks.com/matlabcentral/answers/95334-how-do-i-turn-off-a-particular-warning-in-matlab

MATLAB: How to define a wrapper function to call a built in function such that the wrapper function has the same name as the built-in function

You can utilize the "builtin" function to call the MATLAB built-in "xlswrite" from your overloaded "xlswrite" function. Your "xlswrite" will probably have a format as below:

function [success,theMessage]=xlswrite(file,data,sheet,range) % same structure as built-in "xlswrite"
     % do the pre-processing
     data = ...;
     % call the MATLAB built-in "xlsread"
     builtin('xlswrite', file, data, sheet, range);
end

Following is the documentation link for the "builtin" function that you can refer to:

https://www.mathworks.com/help/matlab/ref/builtin.html

Using this function will result in warning messages, since you are shadowing the MATLAB built-in "xlswrite" function. If you want to turn the warning messages off, you can execute the following commands at the MATLAB Command Window:

warning('off','MATLAB:dispatcher:nameConflict');

On the other hand, to turn the warnings on execute:

warning('on','MATLAB:dispatcher:nameConflict');

Following is the documentation link for "warning" function:

https://www.mathworks.com/help/matlab/ref/warning.html

Best Answer

Related Solutions

MATLAB: How to apply font options when using the LaTeX interpreter in MATLAB

MATLAB: How to define a wrapper function to call a built in function such that the wrapper function has the same name as the built-in function

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