How to insert a nested function by GUI in GUIDE?

I use GUIDE to write a GUI to solve three consecutive differential equations. In the run button, I need to call three additional equation functions, but the three equations cannot be used as m files alone (because the parameters between the three equations are related to each other). Need to be placed as a nested function at the bottom of the gui m file, but the GUI does not seem to recognize the parameters inside the nested function, and use ‘n=str2double(get(handles.edit4,'string'))' , The command found that the input parameters could not be read. What should I do with this situation? Thank you

For example, here is an equation function script for me. In this function, I need to call the result of the previous equation as a parameter and not as an external independent function. Therefore, I can only handle it as a nested function. ，so how can i do it ?

function du=Castor_Collision_2(t,u) 
R=handles.R;      %bold starting here
h=handles.h;
E2=handles.E2;
v2=handles.v2;
rho2=handles.rho2;
E=handles.E;
H1=handles.H1;
H2=handles.H2;
m=handles.m;
n=handles.n;
M=handles.M;
uy=handles.uy;
up=handles.up;   %bold ending here
mu=(m-1)*(u(1)-uy)/(up-uy);
mp=(m-1)/(up-uy);
phi1=sech(mu);
phi2=1-phi1;
phi3=tanh(mu);
H=H1*H2/(2*(H1+H2));            % Kogut模型
alpha=(sqrt(3*(1-v2^2)./(rho2*E2)))./(4*h^2);
g=9.8;
p0=H*g;                 
a=sqrt(R.*u(1));
ap=(3*pi*p0*R)/(4*E);
K2=E*a;
Fmix=phi1*K2*u(1).^n+phi2*p0*pi*(a.^m./(ap^(m-2)));
du=[u(2);alpha*(phi1*phi3*mp*K2*u(1).^n - phi1*K2*n.*u(1).^(n-1) - ...
    phi1*phi3*mp*p0*pi*a^m/ap^(m-2) - phi2*p0*pi*R*m*a^(m-1)/(2*a*ap^(m-2)))*u(2)-(Fmix/M)];
end

[Stephen23]

"What should I do with this situation?"

Avoid GUIDE. Write your own GUI, then you can use nested functions without any issues.

https://www.mathworks.com/matlabcentral/answers/407537-how-can-i-use-the-guide-to-create-an-interface-to-an-existing-program#answer_326390

[Walter Roberson]

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