Hi George,
Looks like you want to solve the “Loss Function” equation using “fsolve”. You have shared a code snippet for the same which seems to be incomplete and some syntactical errors.
Please find the updated code which is complete and flawless:
function lossCalc(app)
% correct way to pass anonymous function which calls lossFunc.
a = fsolve(@(x) lossFunc(x,app), 0.5);
alpha = -2*log(a)/app.Ring_Length;[AK1]
app.Alpha = alpha/100*4.34; % cm
end
function fval = lossFunc(x, app)
app.Q_Intrinsic = pi*app.ng*app.Ring_Length*sqrt(x)/app.lambda0/(1-x);
% lossFunc should also return the value of app.Q_Intrinsic
fval = app.Q_Intrinsic;
end
In this modified version:
- The anonymous function “@(x) lossFunc(x,app)” is passed as the first argument to “fsolve”. This anonymous function takes ‘x’ as the input and calls the “lossFunc” function passing input arguments ‘x’ and “app”(additional argument).
- The “lossFunc” function takes two input arguments, ‘x’ and “app”. It calculates the intrinsic Q factor (app.Q_Intrinsic) based on the given parameters of app and input argument ‘x’.
- The calculated app.Q_Intrinsic value is returned as the output of lossFunc.
You can also adjust the initial guess value (0.5 in this case) passed to “fsolve” as needed. This value should be close to the expected solution for faster convergence.
Please refer the following page to learn more on using “fsolve”:
Hope this helps.
