Failure in initial objective function evaluation. FSOLVE cannot continue
13 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
Hello, i'm trying to solve a nonlinear system of equations and I saw on the web that the function I should be looking for was "fsolve" (I am a beginner MATLAB user). I created my personal function as the following:
C=45.80;
H=5.88 ;
O=46.45 ;
N=1.20 ;
MH=1.008;
MC=12.01;
MO=16.00;
MN=14.01;
ER=0.4;
MC=0.3;
a=(H*MC)/(C*MH);
b=(O*MC)/(C*MO);
c=(N*MC)/(C*MN);
e=((24*MC)/(18*(1-MC)));
f= (ER *(1+(a/4)-(b/2)));
T=725;
lnT=log(T);
K1_m=((7082.848/T)+(-6.567*lnT)+(((7.466*10^-3)/2)*T)+(((-2.164*10^-6)/6)*(T^2))+((0.701*10^5)/(2*(T^2)))+32.541);
K2_wgs=((5870.53/T)+(1.86*lnT)+((-2.7*10^-4)*T)+(-58200/T^2)+(-18.007));
Heres the function am trying to solve
function F = root(x)
F(1) = ((x(3)^2)*k1_m) + x(1) + x(2) - 1;
F(2) = (x(2)*x(3))-((e+(0.5*a)-2)* x(1)* k2_wgs)-(x(1)*x(3)*k2_wgs)+(2*(x(1)^2)*k2_wgs)+(2*(x(1)*x(2))*k2_wgs);
F(3) = (2+(2*f)+b-(0.5*a))-(3*x(1))- (4*x(2))+ (x(3)) ;
end
Then i opened anotherfile to call fsolve
fun=@root;
x0=[1 1];
x= fsolve(fun, x0)
But something is wrong with my code and i get this command box report.
Error: File: root2d.m Line: 33 Column: 14
Function with duplicate name "root2d" cannot be defined.
Error in fsolve (line 242)
fuser = feval(funfcn{3},x,varargin{:});
Error in solved (line 3)
x= fsolve(fun, x0)
Caused by:
Failure in initial objective function evaluation. FSOLVE cannot continue.
0 commentaires
Réponses (1)
Alex Sha
le 9 Avr 2020
You have three equations with three unknown parametrs, but initial start-values, you provide two only (x0=[1 1];), is this your problems?
1 commentaire
Voir également
Catégories
En savoir plus sur Systems of Nonlinear Equations dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!