Failure in solving nonlinear system of equations by using TRESNEI.

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Van Darkholme 2021-5-13

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/828998-failure-in-solving-nonlinear-system-of-equations-by-using-tresnei

Hello, I'm trying to solve a nonlinear system of equations and I saw in a paper that the function I should be looking for was "TRESNEI" (I am a beginner MATLAB user).

I created a function as following:

function F = myfun_unsaturation(x)
global W;
global n;
global m;
global lambda;
global Ptr;
global Ps;
global T;
global slot;
global Ts;
global Tc;
t = x(1);
p = x(2);
q = x(3);
Ptr = 1-(1-t)^n;
Ps = n*t*(1-t)^(n-1)/Ptr;
T = (1-Ptr)*slot + Ptr*Ps*Ts + Ptr*(1-Ps)*Tc
F(1) = 1/((1-q) + q^2*W*(W+1)/(2*(1-(1-q)^W)) + q*(W+1)/(2*(1-q))*(q^2*W/(1-(1-q)^W)+p*(1-q)-q*(1-p)^2) + ...
    p*q^2/(2*(1-q)*(1-p))*(W/(1-(1-q)^W)-(1-p)^2)*(2*W*(1-p-p*(2*p)^(m-1))/(1-2*p)+1))*q^2/(1-q)*(W/((1-p)*(1-(1-q)^W))-(1-p))-t;
F(2) = (1-t)^(n-1)+p-1;
F(3) = 1-exp((-1)*lambda*T)-q;
F = F';
return

When I call solve:

[x,ierr,output] = TRESNEI([0.3,0.2,0.3],[3,0],'myfun_unsaturation',-l,u,options);

The program ends with:

Misuse /
Matrix dimensions must be consistent.
Error tresnei (line 431)
rhof = (Fnrmxpp^2-Fnrm2)*0.5/(grad'*p+0.5*norm(jac*p)^2);
Error test_ TRESNEI (line 55)
[x,ierr,output] = TRESNEI([0.3,0.2,0.3],[3,0],'myfun_ unsaturation',-l,u,options);