IF statement not executing
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% Value changed function: ActionDropDown_2
function ActionDropDown_2ValueChanged(app, event)
if app.ActionDropDown_2.Value == "Plot"
app.Tbl = app.UITable2.Data(:,{'DATE', 'AVAILABILITY'});
app.X = app.UITable2.Data(:,3);
app.Y = app.UITable2.Data(:,31);
plot(app.UIAxes,app.X,app.Y)
end
end
The callback function operates as expected, once called, the debug arrow reaches breakpoint of the IF statment line but once I chose to "Continue" the debug arrow jumps straight to END. Not executing any of the following lines to define Tbl, X, or Y and no plot.
6 个评论
shnrndll
2022-1-5
Voss
2022-1-5
Seems like app.ActionDropDown_2.Value is not equal to "Plot".
shnrndll
2022-1-5
Cris LaPierre
2022-1-5
The code is syntatically correct, and you are not getting any errors. The issue is that the condition evaluates as false, so the code inside the statement does not get run.
shnrndll
2022-1-5
Walter Roberson
2022-1-5
Put a breakpoint at the if. When you arrive there, command
class(app.ActionDropDown_2.Value)
if char(app.ActionDropDown_2.Value)
disp('char')
disp(double(app.ActionDropDown_2.Value))
elseif isstring(app.ActionDropDown_2.Value)
disp('string')
disp(double(app.ActionDropDown_2.Value{1}))
else
disp('other')
disp(app.ActionDropDown_2.Value)
end
and tell us what the output is.
This is not intended as permanent code: it is only intended to help debug the problem.
采纳的回答
Image Analyst
2022-1-5
You need to check the index of the drop down list, or else get the selected string and compare the that string (only) to "Plot" using the contains() function:
% Value changed function: ActionDropDown_2
function ActionDropDown_2ValueChanged(app, event)
% Check the index of the selected item.
selectedIndex = app.ActionDropDown_2.Value;
% Method #1:
%if selectedIndex == 3 % or whatever number in the list it is.
% Rest of "if" block follows...
% Or use Method #2:
% Check the selected string. First get all strings in the list.
allStrings = app.ActionDropDown_2.String;
% Get the specific one that was selected.
selectedString = allStrings{selectedIndex};
% See if it says "Plot".
if contains(selectedString, "Plot", 'IgnoreCase', true)
% They chose plot, so do the plotting.
app.Tbl = app.UITable2.Data(:,{'DATE', 'AVAILABILITY'});
app.X = app.UITable2.Data(:,3);
app.Y = app.UITable2.Data(:,31);
plot(app.UIAxes,app.X,app.Y)
end
end
3 个评论
Image Analyst
2022-1-6
What do you notice if we simplify it to
app.X = app.UITable2.Data(:,3);
app.Y = app.UITable2.Data(:,31);
whos app.X % Look in command window for this
whos app.Y % Look in command window for this
app.s = scatter(app.X, app.Y); % Might plot in some different axes control though
What do you see in the command window, and on your GUI? The data types should be there inthe command window, plus any error messages.
shnrndll
2022-1-6
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