Issue with if else elseif and while
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My appdesigner code begins by writing the first set of answers to file. The first set of answers start on tab press (i.e., on tab press = instruction and question loads; client selects answers, client presses submit). The first set of answers are written when the SubmitAnswers button is pressed. The 'if loop' then presents the remaining questions and writes these to file. I'm having an issue with the "if statement". When I use <=, the app presents all the remaining questions but I get a "row index exceeds table dimensions' error which makes sense because the row index would be 9. However, the app should not process this and should instead go to the elseif statement but the app won't go to the "elseif statement" and process the questions from the next sheet. I've also tried < but then the app only does up to question 7 and misses the last question. I tried "WriteMode Append" but this command appends all answers and I only want the client's answers for one set of questionnaires in the app. If anyone can be of assistance, I would appreciate it. Someone told me that if I read the table in and write it out again, the rows would append. This also is not working in my code below.
% Button pushed function: SubmitAnswersButton
function SubmitAnswersButtonPushed(app, event)
readtable("Answers.xlsx","ReadVariableNames",false,"Sheet","NEQA");
writetable(app.Answers, 'Answers.xlsx', 'Sheet', "NEQA"); %, 'WriteMode', 'Append'); % write the values to the table Answers.xlsx as a backup - should be all questions from all sheets to one page
writetable(app.Answers, app.filenm, 'Sheet', "NEQA"); %, 'WriteMode', 'Append'); % write the answers to the client's excel file;
% collects answers when "Submit" button pushed and writes question and answers to file
if app.NEQCurrentCount < app.NumberOfNEQQuestions
app.NEQCurrentCount = app.NEQCurrentCount + 1; % NEQ question counter
app.NEQsheet_counter = 1; % first sheet in Questionnaires_NEQ.xlsx
app.Answers = table;
%load next question
app.NEQColumns = 3:2:width(app.NEQQuestions);
app.NEQInstructions = readtable('Questionnaires_NEQ.xlsx',"ReadVariableNames",false,"TextType","string","Range","A1"); %height will not work unless readtable comes first; % Succeeds because the sheet counter is a scalar
app.NumberOfNEQInstructions = height(app.NEQInstructions); % total number of instructions; just in case future projects require more rows for instructions;
app.NEQInstructionsTextArea.Value = app.NEQInstructions{1,1}; % writes the instruction in the front panel box from the row count and column 1
app.NEQQuestions = readtable('Questionnaires_NEQ.xlsx',"ReadVariableNames",false,"TextType","string","Sheet", app.NEQsheet_counter); % Succeeds because the sheet counter is a scalar
app.NEQQuestionsTextArea.Value = app.NEQQuestions{app.NEQCurrentCount,2}; % ROW INDEX ERROR OCCURS HERE
selectedButton1.Text = app.ButtonGroup_NEQF.SelectedObject.Text;
selectedButton2.Text = app.ButtonGroup_NEQT.SelectedObject.Text;
selectedButton3.Text = app.ButtonGroup_NEQE.SelectedObject.Text;
newRow = {app.NEQQuestionsTextArea.Value{1}, [selectedButton1.Text], [selectedButton2.Text], [selectedButton3.Text]};
app.Answers = [app.Answers; newRow]; % inserts new row in answer 'file'
readtable("Answers.xlsx","ReadVariableNames",false,"Sheet","NEQA")
writetable(app.Answers, 'Answers.xlsx', 'Sheet', "NEQA");%, 'WriteMode', 'Append'); % write the values to the table Answers.xlsx as a backup - should be all questions from all sheets to one page
writetable(app.Answers, app.filenm, 'Sheet', "NEQA"); % 'WriteMode', 'Append'); % write the answers to the client's excel file; writes the question in the front panel box from the row count and column 2
app.DummyButton1.Value = 1;
app.DummyButton2.Value = 1;
app.DummyButton3.Value = 1;
% Presents Questions for Sheet 2
elseif (app.NEQCurrentCount > app.NumberOfNEQQuestions) % if the question counter is less than the number of questions
app.NEQsheet_counter = app.NEQsheet_counter + 1;
more code
end
end
采纳的回答
Geoff Hayes
2020-4-24
frakenberry - the problem might be the first line in the body of the if statement
if app.NEQCurrentCount < app.NumberOfNEQQuestions
app.NEQCurrentCount = app.NEQCurrentCount + 1; % NEQ question counter
where app.NEQCurrentCount is immediately incremented by one. Can this be the last statement in this body?
if app.NEQCurrentCount <= app.NumberOfNEQQuestions
app.NEQsheet_counter = 1; % first sheet in Questionnaires_NEQ.xlsx
app.Answers = table;
%etc.
app.NEQCurrentCount = app.NEQCurrentCount + 1; % NEQ question counter
elseif (app.NEQCurrentCount > app.NumberOfNEQQuestions)
app.NEQsheet_counter = app.NEQsheet_counter + 1;
% etc.
end
I guess it all depends upon what NEQCurrentCount has been initialized to - zero or one? And do we ever need to reset this counter (like when we change sheets)?
I'm also wondering about
app.NEQsheet_counter = 1; % first sheet in Questionnaires_NEQ.xlsx
. Doesn't this automatic reset to one conflict with the code in the body of the elseif?
app.NEQsheet_counter = app.NEQsheet_counter + 1;
Finally, you mention The 'if loop' then presents the remaining questions and writes these to file. This isn't a "loop". Do you want to be using a loop (with for or while)?
8 个评论
frankenberry
2020-4-24
Geoff Hayes
2020-4-24
But you see how
if app.NEQCurrentCount <= app.NumberOfNEQQuestions
app.NEQCurrentCount = app.NEQCurrentCount + 1; % NEQ question counter
might be a problem for when app.NEQCurrentCount == app.NumberOfNEQQuestions? Because we immediately increment this value by one and so it is now 9 within the body of the if statement and so the
app.NEQQuestionsTextArea.Value = app.NEQQuestions{app.NEQCurrentCount,2};
will fail with an index error (presumably this is the line that throws the error). That's why I suggest incrementing this counter as the last line of the if statement...so that next time we enter the SubmitAnswersButtonPushed callback, the counter will be greater than 8 and we will enter the elseif workflow. In fact the elseif can be removed and just replaced with an else as
if app.NEQCurrentCount <= app.NumberOfNEQQuestions
app.NEQsheet_counter = 1; % first sheet in Questionnaires_NEQ.xlsx
app.Answers = table;
%etc.
%.
%.
app.NEQCurrentCount = app.NEQCurrentCount + 1; % <-- LAST LINE
else
app.NEQsheet_counter = app.NEQsheet_counter + 1;
app.NEQCurrentCount = 1; % <--- maybe??
% etc.
end
frankenberry
2020-4-24
Geoff Hayes
2020-4-25
Hope all is well in NS - it's been an awful week there.
Your second line in the else
app.NEQCurrentCount <= app.NumberOfNEQQuestions; % if the question counter is less than the number of questions
doesn't seem to serve any purpose. Should it do something?
As for resetting to the first page, you did remove the line
app.NEQsheet_counter = 1; % first sheet in Questionnaires_NEQ.xlsx
from the if body? I think that you mentioned you commented it out, but it does need to be removed.
I suspect there is also some duplication in the if and else bodies...this may cause problems the next time the callback is called. I would remove all the duplicated code to outside of the two blocks.
frankenberry
2020-4-25
Geoff Hayes
2020-4-25
Setting it to two should work... but we were already incrementing by one so that should have been the same (?). could use the debugger to figure out what is going on
frankenberry
2020-4-25
编辑：frankenberry
2020-4-25
Geoff Hayes
2020-4-25
if you want to use a for loop, then you could do something like
for k = 1:app.NumberOfNEQQuestions
app.NEQCurrentCount = k; % NEQ question counter
% some code
end
once that is complete then you would move on to the next sheet (and so you would need to indicate somehow that the sheet number has changed. As for the code in the for loop it would be similar to what you have above but you probably wouldn't have to continually read from the Excel file - you would just do that once, and then add each question, and then update the file.
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