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Asking multiple questions to user

Asked by Emma Sellers on 22 Nov 2019 at 14:15
Latest activity Commented on by Image Analyst
on 22 Nov 2019 at 18:34
Hi, Can someone tell me how to ask the user multiple questions while also have one question that changes variables? I want the question below to be an array with 3 different questions.. Is this possible? Thanks!
while B < nodes
B = B+1;
Resistances =inputdlg(['Enter resistance between ',num2str(A),' and ',num2str(B),' or click Ok for infinite resistance.','If resistors in parallel share nodes, Resistance 1:','Resistance 2:']); %changed
if isempty(Resistances(1,2))
if strcmp(Resistances, {''}) % changed... when a user clicks "okay", "Resistances" would have an empty cell
ResistanceMat(A,B) = inf % added... the corresponding element in the matrix is converted to inf, without this it converted to NaN which is not usable in the equation
ResistanceMat(B,A) = inf % added
else
ResistanceMat(A,B) = str2double(Resistances)
ResistanceMat(B,A) = str2double(Resistances)
end

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1 Answer

Answer by Image Analyst
on 22 Nov 2019 at 15:08

Here's a snippet that asks 2 questions. Make the obvioius modifications to change it to three questions.
% Ask user for two floating point numbers.
defaultValue = {'45.67', '78.91'};
titleBar = 'Enter a value';
userPrompt = {'Enter floating point number 1 : ', 'Enter floating point number 2: '};
caUserInput = inputdlg(userPrompt, titleBar, 1, defaultValue);
if isempty(caUserInput),return,end % Bail out if they clicked Cancel.
% Convert to floating point from string.
usersValue1 = str2double(caUserInput{1})
usersValue2 = str2double(caUserInput{2})
% Check usersValue1 for validity.
if isnan(usersValue1)
% They didn't enter a number.
% They clicked Cancel, or entered a character, symbols, or something else not allowed.
% Convert the default from a string and stick that into usersValue1.
usersValue1 = str2double(defaultValue{1});
message = sprintf('I said it had to be a number.\nTry replacing the user.\nI will use %.2f and continue.', usersValue1);
uiwait(warndlg(message));
end
% Do the same for usersValue2
% Check usersValue2 for validity.
if isnan(usersValue2)
% They didn't enter a number.
% They clicked Cancel, or entered a character, symbols, or something else not allowed.
% Convert the default from a string and stick that into usersValue2.
usersValue2 = str2double(defaultValue{2});
message = sprintf('I said it had to be a number.\nTry replacing the user.\nI will use %.2f and continue.', usersValue2);
uiwait(warndlg(message));
end

  2 Comments

Emma Sellers on 22 Nov 2019 at 16:29
This does not work when your asking a question with a changing variable in it.
Image Analyst
on 22 Nov 2019 at 18:34
Why not? I'm not sure what "a changing variable" means. You can certainly use sprintf() to write the current value of a variable into the userPrompt strings. AND, the user is certainly able to change those default variables in the dialog box. AND, you can even take the user's entries and make changes to those. So exactly what does "does not work" mean to you?

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