Failure in initial objective function evaluation. FSOLVE cannot continue

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.

Answer 1

[Alex Sha]

You have three equations with three unknown parametrs, but initial start-values, you provide two only (x0=[1 1];), is this your problems?

[osatohanmwen Evbuomwan]

Hi Alex , i tried using x0=[1 1 1];. it executed an error. i dont know where the error is coming from thats why i need assitance to help me figure that

Attempt to execute SCRIPT root2d as a function:

/Users/Desktop/matlab script/root2d.m

Error in fsolve (line 242)

fuser = feval(funfcn{3},x,varargin{:});

Error in solved (line 32)

x= fsolve(fun, x0)

Caused by:

Failure in initial objective function evaluation. FSOLVE cannot continue.