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Error using a function in App Designer, not returning the correct value.

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George Fryda
George Fryda 2019 年 11 月 1 日
コメント済み: Jyotsna Talluri 2019 年 11 月 7 日
I am attempting to create an fsolve function inside of an app in the App Designer tool.
methods (Access = private)
function Deceleration = SolveForDecel(~,UTF,HB,HT,L,LB,LT,WC,WT,PHI,CHI,PSI,PSIT)
fun = @(x) x*(1+PHI)*(1+WC/(WC+WT))/((1-PSI+x*CHI)-(WC/(WC-WT))*((1-PSIT)*LB/L+x*((HT/LT-HB/LT)*LB/L-HB/L)))-UTF;
x = fzero(fun,.1);
Deceleration = x;
methods (Access = private)
% Callback function: SolveforDecelerationButton, UIFigure
function UIFigureKeyPress(app, event)
valuefordecel = SolveForDecel(app,app.TireRoadfrictioncoefficientEditField.Value, ...
app.GroundhitchballEditField.Value, ...
app.GroundcgtrailerEditField.Value, ...
app.WheelbaseofcarEditField.Value, ...
app.RearaxlecarhitchballEditField.Value, ...
app.TraileraxlehitchballEditField.Value, ...
app.WeightofcarEditField.Value, ...
app.WeightoftrailerEditField.Value, ...
app.RearbrakeFtotalbrakeFEditField.Value, ...
app.cgheightcarwheelbaseEditField.Value, ...
app.rearaxlenotrailerweightEditField.Value, ...
app.DecelerationofCombinationEditField.Value = valuefordecel;
I believe the event is being triggered, and then it runs into an issue in the Fsolve (these are the outputs):
Exiting fzero: aborting search for an interval containing a sign change
because NaN or Inf function value encountered during search.
(Function value at -1.15052e+308 is NaN.)
Check function or try again with a different starting value.
Error using matlab.ui.control.internal.model.AbstractNumericComponent/set.Value (line 185)
'Value' must be a double scalar within the range of 'Limits'.
Error in Trailer_Dynamic_Simulation_Model/UIFigureKeyPress (line 79)
app.DecelerationofCombinationEditField.Value = valuefordecel;
Error using matlab.ui.control.internal.controller.ComponentController/executeUserCallback (line 335)
Error while evaluating Button PrivateButtonPushedFcn.
I am at a loss to determine exactly what the solution is. When I manually run through the function in the command window with realistic values it solves to .3014, which makes sense.
The error it is reading out in App Designer is:

  3 件のコメント

Cris LaPierre
Cris LaPierre 2019 年 11 月 2 日
It would be easier to provide assistance if you share the app. Is that possible? If not, perhaps provide what realistic values for the inputs should be.
George Fryda
George Fryda 2019 年 11 月 4 日
Of course. It won't let me attach the App file, it doesn't support .mlapps, but realistic values may be seen here:
matlab realistic values.PNG
In particular, these are the values that fed correctly into the function when i did it in the command vindow, and worked - giving x as [.3014].
(Chi needed to be CHI)
Guillaume 2019 年 11 月 6 日
What are the values of the inputs that trigger the error?

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回答 (1 件)

Jyotsna Talluri
Jyotsna Talluri 2019 年 11 月 6 日
The possible cause of error may be because of using 'Edit Field(Text)' instead of 'Edit Field (Numeric)'.Make sure you are using the 'Edit Field(Numeric)'.It worked for me when I reproduced it with your given inputs and equation as shown in the attched figure

  2 件のコメント

George Fryda
George Fryda 2019 年 11 月 6 日
Thank you for the suggestions Jyotsna,
I cannot find exactly where this would be in the code. In the place where the inputs are being declared appears to already specify that they are numeric.
% Create GroundcgtrailerEditField
app.GroundcgtrailerEditField = uieditfield(app.UIFigure, 'numeric');
app.GroundcgtrailerEditField.Limits = [0 Inf];
app.GroundcgtrailerEditField.Position = [179 661 100 22];
Is there somewhere else?
Jyotsna Talluri
Jyotsna Talluri 2019 年 11 月 7 日
If you are declaring the inputs through the Numeric edit fields ,the it should work fine.Can you share the entire code in a .m file and the app layout screenshot so that I can check once?

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