How to use message box?

I have some code that works out the y value of the first point on my graph where x>6. This is the 'failure' point.

figure
plot(x,y), hold all
failure=find(x>6,1);

I want to the display whatever this y_value is in a message box on the figure. Any ideas?

Answer 1

[Adam]

doc msgbox

has numerous examples. It is very simple to use, but if you have any questions after looking at that page then feel free to ask those.

[Joe Smith]

Thanks, I've read through these but I don't understand how I can get it to display the number that 'failure=find(x>6,1);' creates.

If I did msgbox('failure') it would just display the word 'failure' in the box.

[Adam]

failNumber = find(x>6,1);

msg = ['failure: ' num2str( failNumber )];
msgbox( msg );

Or however you want to format your message.

Answer 2

[Image Analyst]

Try this

% Find first element where x exceeds 6
index = find(x>6, 1, 'first');
% Get the x and y values for that index
x6 = x(index);
y6 = y(index);
% Make up a message to put on the plot:
message = sprintf('Failed at (x,y) = (%f, %f)', x6, y6);
% Place the message in a text box near the x,y point:
text(x6, y6, message, 'FontSize', 14);

[Image Analyst]

If you want a popup message box instead of a text label sitting on your plot axes, use

uiwait(helpdlg(message));