How to enter data from a GUI (?) rather than in code.

How can I start a program running then, at some point dictated by the code, ask for user input such as a number or a choice of "do this or do that". (I am not sure if it is a "GUI" that I am needing.) So far I only know how to input data through the code. Jonathan.

Answer 1

[Walter Roberson]

input() to ask from the command prompt. inputdlg() for graphical work.

[Jonathan Pulman]

Thank you Walter. I taught myself QBasic years ago but now it is obsolete. I find the very basic things in Matlab documentation hard to understand. Examples of code provided often contain in them other things which confuse me like "twister" concerning random numbers. I look up "random" then I see "twister" so then I am trying to understand "twister" and I go in circles.

It is hard to get info if I don't know the words to search for. Matlab is really superb but my lack of basic knowledge is a problem. I find the online community really helpful; one question here saves two hours of frustration. Thank you again, Jonathan.

[Iain]

uigetfile, uiputfile, & uigetdir will help too.

Answer 2

[Image Analyst]

Here's a snippet. Feel free to modify:

% Ask user for a number.
defaultValue = 45;
titleBar = 'Enter a value';
userPrompt = 'Enter the integer';
caUserInput = inputdlg(userPrompt, titleBar, 1, {num2str(defaultValue)});
if isempty(caUserInput),return,end; % Bail out if they clicked Cancel.
% Round to nearest integer in case they entered a floating point number.
integerValue = round(str2double(cell2mat(caUserInput)));
% Check for a valid integer.
if isnan(integerValue)
    % They didn't enter a number.  
    % They clicked Cancel, or entered a character, symbols, or something else not allowed.
    integerValue = defaultValue;
    message = sprintf('I said it had to be an integer.\nI will use %d and continue.', integerValue);
    uiwait(warndlg(message));
end

[Jonathan Pulman]

This will be helpful. It is new for me but it looks like I will be able learn from it. New but not unintelligible!

Thank you. Jonathan.

[Image Analyst]

If you want to take a look at a nice framework where most stuff is done for you, check this out: http://www.mathworks.com/matlabcentral/fileexchange/24224-magic-matlab-generic-imaging-component. Please mark the best answer as "Accepted" (you can only mark one as such).